Researcher Database

Kohsuke Kudo
Faculty of Medicine Internal Medicine Department of Radiology
Professor

Researcher Profile and Settings

Affiliation

  • Faculty of Medicine Internal Medicine Department of Radiology

Job Title

  • Professor

Degree

  • PhD(2003/03 Hokkaido University)

J-Global ID

Research Interests

  • 神経放射線診断 CT MRI   Neuroradiology CT Perfusion MR Perfusion   

Research Areas

  • Life sciences / Radiology

Educational Organization

Academic & Professional Experience

  • 2019/08 - Today Hokkaido University Graduate School of Medicine Department of Diagnostic Imaging Professor
  • 2013/04 - 2019/07 Hokkaido University Hospital Department of Diagnostic and Interventional Radiology Associate Professor
  • 2011/04 - 2013/03 Iwate Medical University Assistant Professor
  • 2008/04 - 2011/03 Iwate Medical University Advanced Medical Science Research Center Lecturer
  • 2007/04 - 2008/03 Hokkaido University Hospital Department of Radiology Assistant Professor
  • 2006/05 - 2007/03 Wayne State University Visiting Assistant Professor
  • 2004/04 - 2006/04 Hokkaido Univeristy Graduate School of Medicine Department of Radiology Assistant Professor

Education

  • 1999/04 - 2003/03  Hokkaido University  Graduate School of Medicine  Department of Radiology
  • 1989/04 - 1995/03  Hokkaido University  School of Medicine

Association Memberships

  • Japan Society for CNS Computed Imaging   Japanese Society of Cerebral Blood Flow and Metabolism   International Society for Magnetic Resonance in Medicine   Japanese Society for Magnetic Resonance in Medicine   The Japanese Society of Neuroradiology   Radiological Society of North America   Japan Radiological Society   

Research Activities

Published Papers

  • Minghui Tang, Taku Sugiyama, Ren Takahari, Hiroyuki Sugimori, Takaaki Yoshimura, Katsuhiko Ogasawara, Kohsuke Kudo, Miki Fujimura
    Neurosurgical review 47 (1) 200 - 200 2024/05/09 
    Appropriate needle manipulation to avoid abrupt deformation of fragile vessels is a critical determinant of the success of microvascular anastomosis. However, no study has yet evaluated the area changes in surgical objects using surgical videos. The present study therefore aimed to develop a deep learning-based semantic segmentation algorithm to assess the area change of vessels during microvascular anastomosis for objective surgical skill assessment with regard to the "respect for tissue." The semantic segmentation algorithm was trained based on a ResNet-50 network using microvascular end-to-side anastomosis training videos with artificial blood vessels. Using the created model, video parameters during a single stitch completion task, including the coefficient of variation of vessel area (CV-VA), relative change in vessel area per unit time (ΔVA), and the number of tissue deformation errors (TDE), as defined by a ΔVA threshold, were compared between expert and novice surgeons. A high validation accuracy (99.1%) and Intersection over Union (0.93) were obtained for the auto-segmentation model. During the single-stitch task, the expert surgeons displayed lower values of CV-VA (p < 0.05) and ΔVA (p < 0.05). Additionally, experts committed significantly fewer TDEs than novices (p < 0.05), and completed the task in a shorter time (p < 0.01). Receiver operating curve analyses indicated relatively strong discriminative capabilities for each video parameter and task completion time, while the combined use of the task completion time and video parameters demonstrated complete discriminative power between experts and novices. In conclusion, the assessment of changes in the vessel area during microvascular anastomosis using a deep learning-based semantic segmentation algorithm is presented as a novel concept for evaluating microsurgical performance. This will be useful in future computer-aided devices to enhance surgical education and patient safety.
  • Satoru Aono, Satonori Tsuneta, Noriko Nishioka, Takuya Aoike, Hiroyuki Hirayama, Kinya Ishizaka, Jihun Kwon, Masami Yoneyama, Noriyuki Fujima, Kohsuke Kudo
    Magnetic resonance in medical sciences : MRMS : an official journal of Japan Society of Magnetic Resonance in Medicine 2024/03/29 
    PURPOSE: Prolonged scanning of time-resolved 3D phase-contrast MRI (4D flow MRI) limits its routine use in clinical practice. An echo-planar imaging (EPI)-based sequence and compressed sensing can reduce the scan duration. We aimed to determine the impact of EPI for 4D flow MRI on the scan duration, image quality, and quantitative flow metrics. METHODS: This was a prospective study of 15 healthy volunteers (all male, mean age 33 ± 5 years). Conventional sensitivity encoding (SENSE), EPI with SENSE (EPI), and compressed SENSE (CS) (reduction factors: 6 and 12, respectively) were scanned.Scan duration, qualitative indexes of image quality, and quantitative flow parameters of net flow volume, maximum flow velocity, wall shear stress (WSS), and energy loss (EL) in the ascending aorta were assessed. Two-dimensional phase-contrast cine MRI (2D-PC) was considered the gold standard of net flow volume and maximum flow velocity. RESULTS: Compared to SENSE, EPI and CS12 shortened scan durations by 71% and 73% (EPI, 4 min 39 sec; CS6, 7 min 29 sec; CS12, 4 min 14 sec; and SENSE, 15 min 51 sec). Visual image quality was significantly better for EPI than for SENSE and CS (P < 0.001). The net flow volumes obtained with SENSE, EPI, and CS12 and those obtained with 2D-PC were correlated well (r = 0.950, 0.871, and 0.850, respectively). However, the maximum velocity obtained with EPI was significantly underestimated (P < 0.010). The average WSS was significantly higher with EPI than with SENSE, CS6, and CS12 (P < 0.001, P = 0.040, and P = 0.012, respectively). The EL was significantly lower with EPI than with CS6 and CS12 (P = 0.002 and P = 0.007, respectively). CONCLUSION: EPI reduced the scan duration, improved visual image quality, and was associated with more accurate net flow volume than CS. However, the flow velocity, WSS, and EL values obtained with EPI and other sequences may not be directly comparable.
  • Masahito Kawabori, Satoshi Kuroda, Hideo Shichinohe, Kaoru Kahata, Souichi Shiratori, Satoshi Ikeda, Taisuke Harada, Kenji Hirata, Khin Khin Tha, Masato Aragaki, Shunsuke Terasaka, Yoichi M Ito, Naoki Nishimoto, Shunsuke Ohnishi, Ichiro Yabe, Kohsuke Kudo, Kiyohiro Houkin, Miki Fujimura
    Med (New York, N.Y.) 2024/03/18 
    BACKGROUND: Ischemic stroke is one of the leading causes of death and neurological disability worldwide, and stem cell therapy is highly expected to reverse the sequelae. This phase 1/2, first-in-human study evaluated the safety, feasibility, and monitoring of an intracerebral-transplanted magnetic resonance imaging (MRI)-trackable autologous bone marrow stromal cell (HUNS001-01) for patients with subacute ischemic stroke. METHODS: The study included adults with severe disability due to ischemic stroke. HUNS001-01 cultured with human platelet lysates and labeled with superparamagnetic iron oxide was stereotactically transplanted into the peri-infarct area 47-64 days after ischemic stroke onset (dose: 2 or 5 × 107 cells). Neurological and radiographic evaluations were performed throughout 1 year after cell transplantation. The trial was registered at UMIN Clinical Trial Registry (number UMIN000026130). FINDINGS: All seven patients who met the inclusion criteria successfully achieved cell expansion, underwent intracerebral transplantation, and completed 1 year of follow-up. No product-related adverse events were observed. The median National Institutes of Health Stroke Scale and modified Rankin scale scores before transplantation were 13 and 4, which showed improvements of 1-8 and 0-2, respectively. Cell tracking proved that the engrafted cells migrated toward the infarction border area 1-6 months after transplantation, and the quantitative susceptibility mapping revealed that cell signals at the migrated area constantly increased throughout the follow-up period up to 34% of that of the initial transplanted site. CONCLUSIONS: Intracerebral transplantation of HUNS001-01 was safe and well tolerated. Cell tracking shed light on the therapeutic mechanisms of intracerebral transplantation. FUNDING: This work was supported by the Japan Agency for Medical Research and Development (AMED; JP17bk0104045 and JP20bk0104011).
  • Hiroyuki Kameda, Yumi Nakada, Yuta Urushibata, Hiroyuki Sugimori, Takaaki Fujii, Naoya Kinota, Daisuke Kato, Minghui Tang, Keita Sakamoto, Kohsuke Kudo
    Magnetic resonance in medical sciences : MRMS : an official journal of Japan Society of Magnetic Resonance in Medicine 2024/03/15 
    17O-labeled water is a T2-shortening contrast agent used in proton MRI and is a promising method for visualizing cerebrospinal fluid (CSF) dynamics because it provides long-term tracking of water molecules. However, various external factors reduce the accuracy of 17O-concentration measurements using conventional signal-intensity-based methods. In addition, T2 mapping, which is expected to provide a stable assessment, is generally limited to temporal-spatial resolution. We developed the T2-prepared based on T2 mapping used in cardiac imaging to adapt to long T2 values and tested whether it could accurately measure 17O-concentration in the CSF using a phantom. The results showed that 17O-concentration in a fluid mimicking CSF could be evaluated with an accuracy comparable to conventional T2-mapping (Carr-Purcell-Meiboom-Gill multi-echo spin-echo method). This method allows 17O-imaging with a high temporal resolution and stability in proton MRI. This imaging technique may be promising for visualizing CSF dynamics using 17O-labeled water.
  • Sho Kazui, Sakae Takenaka, Toshiyuki Nagai, Satonori Tsuneta, Kenji Hirata, Yoshiya Kato, Hirokazu Komoriyama, Yuta Kobayashi, Akinori Takahashi, Kiwamu Kamiya, Taro Temma, Takuma Sato, Atsushi Tada, Yutaro Yasui, Michikazu Nakai, Takahiro Sato, Ichizo Tsujino, Kohsuke Kudo, Satoshi Konno, Toshihisa Anzai
    JACC. Cardiovascular imaging 2024/03/11
  • Satonori Tsuneta, Kenichiro Suno, Yuichiro Fujieda, Masaya Watanabe, Shiro Watanabe, Kenji Hirata, Toshiyuki Nagai, Kohsuke Kudo
    Canadian Journal of Cardiology 2024/03 [Refereed][Not invited]
  • Noriyuki Fujima, Junichi Nakagawa, Yohei Ikebe, Hiroyuki Kameda, Taisuke Harada, Yukie Shimizu, Nayuta Tsushima, Satoshi Kano, Akihiro Homma, Jihun Kwon, Masami Yoneyama, Kohsuke Kudo
    Magnetic resonance imaging 108 111 - 115 2024/02/09 
    PURPOSE: To assess the utility of deep learning (DL)-based image reconstruction with the combination of compressed sensing (CS) denoising cycle by comparing images reconstructed by conventional CS-based method without DL in fat-suppressed (Fs)-contrast enhanced (CE) three-dimensional (3D) T1-weighted images (T1WIs) of the head and neck. MATERIALS AND METHODS: We retrospectively analyzed the cases of 39 patients who had undergone head and neck Fs-CE 3D T1WI applying reconstructions based on conventional CS and CS augmented by DL, respectively. In the qualitative assessment, we evaluated overall image quality, visualization of anatomical structures, degree of artifacts, lesion conspicuity, and lesion edge sharpness based on a five-point system. In the quantitative assessment, we calculated the signal-to-noise ratios (SNRs) of the lesion and the posterior neck muscle and the contrast-to-noise ratio (CNR) between the lesion and the adjacent muscle. RESULTS: For all items of the qualitative analysis, significantly higher scores were awarded to images with DL-based reconstruction (p < 0.001). In the quantitative analysis, DL-based reconstruction resulted in significantly higher values for both the SNR of lesions (p < 0.001) and posterior neck muscles (p < 0.001). Significantly higher CNRs were also observed in images with DL-based reconstruction (p < 0.001). CONCLUSION: DL-based image reconstruction integrating into the CS-based denoising cycle offered superior image quality compared to the conventional CS method. This technique will be useful for the assessment of patients with head and neck disease.
  • Yuya Hirano, Noriyuki Fujima, Kinya Ishizaka, Takuya Aoike, Junichi Nakagawa, Masami Yoneyama, Kohsuke Kudo
    Cureus 16 (2) e54203  2024/02 
    Purpose This study aimed to compare the image quality between echo planar imaging (EPI) with compressed sensing-sensitivity encoding (EPICS)-based diffusion-weighted imaging (DWI) and conventional parallel imaging (PI)-based DWI of the head and neck. Materials and methods Ten healthy volunteers participated in this study. EPICS-DWI was acquired based on an axial spin-echo EPI sequence with EPICS acceleration factors of 2, 3, and 4, respectively. Conventional PI-DWI was acquired using the same acceleration factors (i.e., 2, 3, and 4). Quantitative assessment was performed by measuring the signal-to-noise ratio (SNR) and apparent diffusion coefficient (ADC) in a circular region of interest (ROI) on the parotid and submandibular glands. For qualitative evaluation, a three-point visual grading system was used to assess the (1) overall image quality and (2) degree of image distortion. Results In the quantitative assessment, the SNR of the parotid gland in EPICS-DWI was significantly higher than that of PI-DWI in acceleration factors of 3 and 4 (p<0.05). In a comparison of ADC values, significant differences were not observed between EPICS-DWI and PI-DWI. In the qualitative assessment, the overall image quality of EPICS-DWI was significantly higher than that of PI-DWI for acceleration factors 3 and 4 (p<0.05). The degree of image distortion was significantly larger in EPICS-DWI with an acceleration factor of 2 than that of 3 or 4 (p<0.01, respectively). Conclusion Under the appropriate parameter setting, EPICS-DWI demonstrated higher SNR and better overall image quality for head and neck imaging than PI-DWI, without increasing image distortion.
  • Junichi Nakagawa, Noriyuki Fujima, Kenji Hirata, Taisuke Harada, Naoto Wakabayashi, Yuki Takano, Akihiro Homma, Satoshi Kano, Kazuyuki Minowa, Kohsuke Kudo
    Japanese journal of radiology 2024/01/27 
    PURPOSE: To develop a convolutional neural network (CNN) model to diagnose skull-base invasion by nasopharyngeal malignancies in CT images and evaluate the model's diagnostic performance. MATERIALS AND METHODS: We divided 100 malignant nasopharyngeal tumor lesions into a training (n = 70) and a test (n = 30) dataset. Two head/neck radiologists reviewed CT and MRI images and determined the positive/negative skull-base invasion status of each case (training dataset: 29 invasion-positive and 41 invasion-negative; test dataset: 13 invasion-positive and 17 invasion-negative). Preprocessing involved extracting continuous slices of the nasopharynx and clivus. The preprocessed training dataset was used for transfer learning with Residual Neural Networks 50 to create a diagnostic CNN model, which was then tested on the preprocessed test dataset to determine the invasion status and model performance. Original CT images from the test dataset were reviewed by a radiologist with extensive head/neck imaging experience (senior reader: SR) and another less-experienced radiologist (junior reader: JR). Gradient-weighted class activation maps (Grad-CAMs) were created to visualize the explainability of the invasion status classification. RESULTS: The CNN model's diagnostic accuracy was 0.973, significantly higher than those of the two radiologists (SR: 0.838; JR: 0.595). Receiver operating characteristic curve analysis gave an area under the curve of 0.953 for the CNN model (versus 0.832 and 0.617 for SR and JR; both p < 0.05). The Grad-CAMs suggested that the invasion-negative cases were present predominantly in bone marrow, while the invasion-positive cases exhibited osteosclerosis and nasopharyngeal masses. CONCLUSIONS: This CNN technique would be useful for CT-based diagnosis of skull-base invasion by nasopharyngeal malignancies.
  • SSPPD後の胆管空腸吻合部閉塞に対するsharp recanalizationによる内外瘻化
    岡村 実幸, 阿保 大介, 森田 亮, 松井 あや, 木野田 直也, 加藤 大祐, 藤井 宝顕, 山崎 康之, 高柳 歩, 若林 直人, 平野 聡, 工藤 與亮
    日本インターベンショナルラジオロジー学会雑誌 (一社)日本インターベンショナルラジオロジー学会 38 (3) 221 - 221 1340-4520 2024/01
  • Noriko Nishioka, Yukie Shimizu, Toru Shirai, Hisaaki Ochi, Yoshitaka Bito, Kiichi Watanabe, Hiroyuki Kameda, Taisuke Harada, Kohsuke Kudo
    Magnetic Resonance in Medical Sciences 1347-3182 2024
  • Hiroyuki Kameda, Naoya Kinota, Daisuke Kato, Takaaki Fujii, Taisuke Harada, Yuji Komaki, Hiroyuki Sugimori, Tomohiro Onodera, Moyoko Tomiyasu, Takayuki Obata, Kohsuke Kudo
    Investigative radiology 59 (1) 92 - 103 2024/01/01 
    Magnetic resonance imaging (MRI) is a crucial imaging technique for visualizing water in living organisms. Besides proton MRI, which is widely available and enables direct visualization of intrinsic water distribution and dynamics in various environments, MR-WTI (MR water tracer imaging) using 17 O-labeled water has been developed, benefiting from the many advancements in MRI software and hardware that have substantially improved the signal-to-noise ratio and made possible faster imaging. This cutting-edge technique allows the generation of novel and valuable images for clinical use. This review elucidates the studies related to MRI water tracer techniques centered around 17 O-labeled water, explaining the fundamental principles of imaging and providing clinical application examples. Anticipating continued progress in studies involving isotope-labeled water, this review is expected to contribute to elucidating the pathophysiology of various diseases related to water dynamics abnormalities and establishing novel imaging diagnostic methods for associated diseases.
  • 片岡 正子, 原田 太以佑, 森下 陽平, 伊良波 裕子, 工藤 與亮
    臨床画像 (株)メジカルビュー社 39 (12) 1449 - 1453 0911-1069 2023/12 
    <文献概要>『画像診断ガイドライン 2021年版』では,想定読者を画像をオーダーする一般診療科の医師にまで広げたが,普及・活用には課題がある。次世代の画像診断ガイドラインにおいて,冊子主体からWeb主体,その一部をアプリ化することでのガイドラインの普及と活用促進が検討されており,最新の情報を交えて報告する。
  • Noriyuki Fujima, Junichi Nakagawa, Hiroyuki Kameda, Yohei Ikebe, Taisuke Harada, Yukie Shimizu, Nayuta Tsushima, Satoshi Kano, Akihiro Homma, Jihun Kwon, Masami Yoneyama, Kohsuke Kudo
    Magma (New York, N.Y.) 2023/11/21 
    OBJECTIVES: To investigate the utility of deep learning (DL)-based image reconstruction using a model-based approach in head and neck diffusion-weighted imaging (DWI). MATERIALS AND METHODS: We retrospectively analyzed the cases of 41 patients who underwent head/neck DWI. The DWI in 25 patients demonstrated an untreated lesion. We performed qualitative and quantitative assessments in the DWI analyses with both deep learning (DL)- and conventional parallel imaging (PI)-based reconstructions. For the qualitative assessment, we visually evaluated the overall image quality, soft tissue conspicuity, degree of artifact(s), and lesion conspicuity based on a five-point system. In the quantitative assessment, we measured the signal-to-noise ratio (SNR) of the bilateral parotid glands, submandibular gland, the posterior muscle, and the lesion. We then calculated the contrast-to-noise ratio (CNR) between the lesion and the adjacent muscle. RESULTS: Significant differences were observed in the qualitative analysis between the DWI with PI-based and DL-based reconstructions for all of the evaluation items (p < 0.001). In the quantitative analysis, significant differences in the SNR and CNR between the DWI with PI-based and DL-based reconstructions were observed for all of the evaluation items (p = 0.002 ~ p < 0.001). DISCUSSION: DL-based image reconstruction with the model-based technique effectively provided sufficient image quality in head/neck DWI.
  • Shiro Watanabe, Kenji Hirata, Keiichi Magota, Junki Takenaka, Naoto Wakabayashi, Daiki Shinyama, Koichi Yasuda, Akihiro Homma, Kohsuke Kudo
    Annals of nuclear medicine 2023/11/09 
    OBJECTIVE: Silicon photomultiplier-based positron emission tomography/computed tomography (SiPM-PET/CT) has the superior spatial resolution to conventional PET/CT (cPET/CT). This head-to-head comparison study compared the images of physiological 18F-fluorodeoxyglucose (FDG) accumulation in small-volume structures between SiPM-PET/CT and cPET/CT in patients scanned with both modalities, and we investigated whether the thresholds that are reported to be useful for differentiating physiological accumulations from malignant lesions can also be applied to SiPM-PET/CT. METHODS: We enrolled 21 consecutive patients with head and neck malignancies who underwent whole-body FDG-PET/CT for initial staging or a follow-up evaluation (October 2020 to March 2022). After being injected with FDG, all patients underwent PET acquisition on both Vereos PET-CT and Gemini TF64 PET-CT systems (both Philips Healthcare) in random order. For each patient, the maximum standardized uptake value (SUVmax) was measured in the pituitary gland, esophagogastric junction (EGJ), adrenal glands, lumbar enlargement of the spinal cord, and epididymis. We measured the liver SUVmean and the blood pool SUVmean to calculate the target-to-liver ratio (TLR) and the target-to-blood ratio (TBR), respectively. Between-groups differences in each variable were examined by a paired t-test. We also investigated whether there were cases of target uptake greater than the reported threshold for distinguishing pathological from physiological accumulations. RESULTS: Data were available for 19 patients. Ten patients were in Group 1, i.e., the patients who underwent SiPM-PET first, and the remaining nine patients who underwent cPET first were in Group 2. In the SiPM-PET results, the SUVmax of all targets was significantly higher than that obtained by cPET in all patients, and this tendency was also observed when the patients were divided into Groups 1/2. The TLRs of all targets were significantly higher in SiPM-PET than in cPET in all patients, and SiPM-PET also showed significantly higher TBRs for all targets except the EGJ (p = 0.052). CONCLUSIONS: The physiological uptake in the small structures studied herein showed high accumulation on SiPM-PET. Our results also suggest that the thresholds reported for cPET to distinguish pathological accumulations likely lead to false-positive findings in SIPM-PET evaluations.
  • 阿保 大介, 森田 亮, 木野田 直也, 加藤 大祐, 藤井 宝顕, 山崎 康之, 高柳 歩, 工藤 與亮
    日本外科感染症学会雑誌 (一社)日本外科感染症学会 20 (3) 289 - 289 1349-5755 2023/11
  • Junki Takenaka, Kenji Hirata, Shiro Watanabe, Masahiko Takahata, Kohsuke Kudo
    Clinical nuclear medicine 48 (11) e523-e525  2023/11/01 
    MRI revealed a thoracic vertebrae lesion in a 40-year-old woman with back pain. She was referred to our institution; MRI demonstrated a mass from the second to the fifth thoracic vertebra and compression fractures. CT revealed a splenic mass, multiple pulmonary nodules, and low-density masses in the liver. 18 F-FDG PET/CT showed increased uptake (SUV max , 10.6) in the peripheral rim of the thoracic vertebra mass, with central parts showing lower uptake than the peripheral rim. The splenic mass exhibited increased accumulation (SUV max , 4.8). The thoracic spine lesion was fixed; a biopsy was performed. Alveolar echinococcosis was confirmed immunologically. Alveolar echinococcosis can present with bone lesions. It must be differentiated from malignancy.
  • Yuki Takahashi, Kiwamu Kamiya, Toshiyuki Nagai, Satonori Tsuneta, Noriko Oyama-Manabe, Takeshi Hamaya, Sho Kazui, Yutaro Yasui, Kohei Saiin, Seiichiro Naito, Yoshifumi Mizuguchi, Sakae Takenaka, Atsushi Tada, Suguru Ishizaka, Yuta Kobayashi, Kazunori Omote, Takuma Sato, Yasushige Shingu, Kohsuke Kudo, Satoru Wakasa, Toshihisa Anzai
    Journal of cardiovascular magnetic resonance : official journal of the Society for Cardiovascular Magnetic Resonance 25 (1) 60 - 60 2023/10/26 
    BACKGROUND: The differences in pre- and early post-procedural blood flow dynamics between the two major types of bioprosthetic valves, the balloon-expandable valve (BEV) and self-expandable valve (SEV), in patients with aortic stenosis (AS) undergoing transcatheter aortic valve replacement (TAVR), have not been investigated. We aimed to investigate the differences in blood flow dynamics between the BEV and SEV using four-dimensional flow cardiovascular magnetic resonance (4D flow CMR). METHODS: We prospectively examined 98 consecutive patients with severe AS who underwent TAVR between May 2018 and November 2021 (58 BEV and 40 SEV) after excluding those without CMR because of a contraindication, inadequate imaging from the analyses, or patients' refusal. CMR was performed in all participants before (median interval, 22 [interquartile range (IQR) 4-39] days) and after (median interval, 6 [IQR 3-6] days) TAVR. We compared the changes in blood flow patterns, wall shear stress (WSS), and energy loss (EL) in the ascending aorta (AAo) between the BEV and SEV using 4D flow CMR. RESULTS: The absolute reductions in helical flow and flow eccentricity were significantly higher in the SEV group compared in the BEV group after TAVR (BEV: - 0.22 ± 0.86 vs. SEV: - 0.85 ± 0.80, P < 0.001 and BEV: - 0.11 ± 0.79 vs. SEV: - 0.50 ± 0.88, P = 0.037, respectively); there were no significant differences in vortical flow between the groups. The absolute reduction of average WSS was significantly higher in the SEV group compared to the BEV group after TAVR (BEV: - 0.6 [- 2.1 to 0.5] Pa vs. SEV: - 1.8 [- 3.5 to - 0.8] Pa, P = 0.006). The systolic EL in the AAo significantly decreased after TAVR in both the groups, while the absolute reduction was comparable between the groups. CONCLUSIONS: Helical flow, flow eccentricity, and average WSS in the AAo were significantly decreased after SEV implantation compared to BEV implantation, providing functional insights for valve selection in patients with AS undergoing TAVR. Our findings offer valuable insights into blood flow dynamics, aiding in the selection of valves for patients with AS undergoing TAVR. Further larger-scale studies are warranted to confirm the prognostic significance of hemodynamic changes in these patients.
  • Type I endoleakに対するコイル塞栓術後の凝固線溶機能変化の検討
    山崎 康之, 山本 真由, 釘宮 愛子, 北川 幹太, 平野 貴規, 市木 純哉, 山本 浩大郎, 和田 武, 臼井 亮介, 木下 光博, 阿保 大介, 近藤 浩史, 工藤 與亮
    脈管学 (一社)日本脈管学会 63 (Suppl.) S176 - S176 0387-1126 2023/10
  • 心臓サルコイドーシス患者におけるガドリニウム遅延造影心臓MRIとFDG-PETを用いた複合的画像評価の予後的意義
    數井 翔, 竹中 秀, 永井 利幸, 常田 慧徳, 加藤 喜哉, 小森山 弘和, 小林 雄太, 高橋 昌寛, 神谷 究, 天満 太郎, 佐藤 琢真, 多田 篤司, 安井 悠太郎, 中井 陸運, 佐藤 隆博, 辻野 一三, 工藤 與亮, 今野 哲, 安斉 俊久
    日本サルコイドーシス/肉芽腫性疾患学会雑誌 日本サルコイドーシス 43 (サプリメント号) 65 - 65 1883-1273 2023/10
  • Junki Takenaka, Shiro Watanabe, Takashige Abe, Takahiro Tsuchikawa, Satoshi Takeuchi, Kenji Hirata, Rina Kimura, Naoto Wakabayashi, Nobuo Shinohara, Kohsuke Kudo
    Neuroendocrinology 2023/09/19 
    Pheochromocytomas and paragangliomas (PPGLs) are rare neuroendocrine tumours that produce catecholamines. [131I] MIBG-avid unresectable or metastatic PPGLs are treated with [131I] MIBG therapy. A high metabolic tumour volume (MTV) and total lesion glycolysis (TLG) can be poor prognostic factors. Therefore, we evaluated the metabolic responses to [131I] MIBG therapy with respect to other clinical factors.A retrospective study was performed on a series of 20 patients who underwent FDG-PET before and after [131I] MIBG therapy. We administered a single dose comprising 5.5 GBq of [131I] MIBG. Semi-quantitative parameters (SUVmax, MTV, and TLG) were calculated using the liver SUV (mean + 3SD) as a threshold on Metavol software. The semi-quantitative FDG-PET parameters for determining response were complete response , partial remission, stable disease, and progressive disease (PD). We divided our study participants into the PD and non-PD groups and compared the overall survival between the two groups. Subsequently, we evaluated the relationships between metabolic response and age, sex, tumour type, metastatic site, chemotherapy or external radiation history, and 24-hour urine catecholamine levels by univariate logistic regression analyses. Both MTV-based and TLG-based criteria for PD vs. non-PD were significant prognostic factors (p = 0.014). However, treatment response as evaluated based on the SUVmax was not a significant predictor. Higher urinary dopamine levels were associated with poor metabolic response as assessed by MTV and TLG. The other clinical parameters were non-significant. Poor metabolic response (measured with MTV and TLG) to [131I] MIBG therapy in unresectable or metastatic PPGLs was related to shorter OS. The poor metabolic response can be predicted using the urinary dopamine level.
  • Yohei Ikebe, Ryota Sato, Tomoki Amemiya, Niki Udo, Masaaki Matsushima, Ichiro Yabe, Akinori Yamaguchi, Makoto Sasaki, Masafumi Harada, Noriyuki Matsukawa, Yasuo Kawata, Yoshitaka Bito, Toru Shirai, Hisaaki Ochi, Kohsuke Kudo
    Magnetic resonance imaging 103 192 - 197 2023/08/08 
    PURPOSE: To develop a method for predicting amyloid positron emission tomography (PET) positivity based on multiple regression analysis of quantitative susceptibility mapping (QSM). MATERIALS AND METHODS: This prospective study included 39 patients with suspected dementia from four centers. QSM images were obtained through a 3-T, three-dimensional radiofrequency-spoiled gradient-echo sequence with multiple echoes. The cortical standard uptake value ratio (SUVR) was obtained using amyloid PET with 18F-flutemetamol, and susceptibility in the brain regions was obtained using QSM. A multiple regression model to predict cortical SUVR was constructed based on susceptibilities in multiple brain regions, with the constraint that cortical SUVR and susceptibility were positively correlated. The discrimination performance of the Aβ-positive and Aβ-negative cohorts was evaluated based on the predicted SUVR using the area under the receiver operating characteristic curve (AUC) and Mann-Whitney U test. RESULTS: The correlation coefficients between true and predicted SUVR were increased by incorporating the constraint, and the AUC to discriminate between the Aβ-positive and Aβ-negative cohorts reached to 0.79 (p < 0.01). CONCLUSION: These preliminary results suggest that a QSM-based multiple regression model can predict amyloid PET positivity with fair accuracy.
  • Atsushi Tada, Toshiyuki Nagai, Yoshiya Kato, Noriko Oyama-Manabe, Satonori Tsuneta, Michikazu Nakai, Yutaro Yasui, Sho Kazui, Yuki Takahashi, Kohei Saiin, Seiichiro Naito, Sakae Takenaka, Yoshifumi Mizuguchi, Yuta Kobayashi, Suguru Ishizaka, Kazunori Omote, Takuma Sato, Takao Konishi, Kiwamu Kamiya, Kohsuke Kudo, Toshihisa Anzai
    The American journal of cardiology 200 115 - 123 2023/08/01 
    Several liver fibrotic markers are associated with prognosis in patients with heart failure (HF). However, the optimal markers for outcome prediction remain unclear. This study aimed to simultaneously investigate the prognostic value of liver fibrotic markers and the associations between these markers and clinical parameters in patients with HF without organic liver disease. We prospectively examined 211 consecutive patients with chronic HF between April 2018 and August 2021, excluding those with organic liver disease, using liver magnetic resonance imaging and ultrasound. A total of 7 representative liver fibrotic markers were measured in all patients. The primary outcome of interest was the composite of all-cause death and hospitalization for worsening HF. During a median follow-up period of 747 (interquartile range 465 to 1,042) days, the primary outcome occurred in 45 patients. Patients with higher hyaluronic acid and type III procollagen N-terminal peptide (P-III-P) levels showed a significantly higher incidence of the primary outcome than those without (p <0.001 and p = 0.005, respectively). The multivariable Cox regression analysis revealed that hyaluronic acid and P-III-P levels were independently associated with the risk of adverse events (hazard ratio 1.84, 95% confidence interval 1.18 to 2.87 and hazard ratio 2.89, 95% confidence interval 1.32 to 6.34, respectively) even after adjustment for a mortality prediction model, whereas the other 5 markers were not associated with the primary outcome. In conclusion, among the representative liver fibrotic markers, hyaluronic acid and P-III-P might be the optimal markers for outcome prediction in patients with HF.
  • 【医療AIの普及拡大とさらなる展開 医療からヘルスケアサービスまで発展に向けた現状と展望】医療AIのための人材育成の現状と展望 北海道大学における医療AI開発者育成プログラムの活動と展望
    唐 明輝, 平田 健司, 杉森 博行, 吉村 高明, 小笠原 克彦, 中谷 純, 工藤 與亮
    INNERVISION (株)インナービジョン 38 (7) 19 - 20 0913-8919 2023/06 
    わが国においては高齢化,医療者の偏在,働き方改革など,多くの医療課題が山積みになっている。それらの課題を解決するため,医療AIの導入および展開が喫緊の課題となっている。そのような背景で,東北大学を主幹に,北海道大学と岡山大学が連携する医療AI人材育成プロジェクト「『Global×Localな医療課題解決を目指した最先端AI研究開発』人材育成教育拠点」が,文部科学省・大学教育再生戦略推進費「保健医療分野におけるAI研究開発加速に向けた人材養成産学協働プロジェクト」に採択された[2020(令和2)~2024(令和6)年度]。北海道大学では,大学院医学研究院連携研究センター医療AI教育研究分野を中心に,東北大学および岡山大学と連携し,協力校である北海道情報大学,北海道科学大学とともに,民間企業や自治体の支援を受けながら,多様性に富んだ事業推進体制による医療AI開発者養成プログラム(Clinical AI Human Resources Development Program:CLAP)を2021(令和3)年度から本格的に展開し始めた。(著者抄録)
  • Naoya Kinota, Hiroyuki Kameda, Bai Xiawei, Takaaki Fujii, Daisuke Kato, Bunya Takahashi, Ryo Morita, Daisuke Abo, Ryusei Majima, Hiroshi Ishii, Kazuyuki Minowa, Kohsuke Kudo
    Magnetic resonance in medical sciences : MRMS : an official journal of Japan Society of Magnetic Resonance in Medicine 2023/05/30 
    PURPOSE: To investigate whether deep cervical lymph node (DCLN) ligation alters intracranial cerebrospinal fluid (CSF) tracer dynamics and outflow using a rat model with intrathecal dynamic contrast-enhanced (DCE) MRI. METHODS: Six bilateral DCLN-ligated and six sham-operated rats were subjected to DCE MRI with Gd-BTDO3A, and dynamic T1-weighted images were acquired. ROIs were collected from the CSF at the C1 level (CSF_C1), CSF between the olfactory bulbs (CSF_OB), CSF at the pituitary recess (CSF_PitR), and CSF at the pineal recess (CSF_PinR), upper nasal turbinate (UNT), olfactory bulbs, cerebrum, and the jugular region. Time-intensity curves were evaluated, and the maximum slope, peak timing, peak signal ratio, and elimination half-life for the four CSF ROIs and UNT were calculated and compared. RESULTS: Delayed tracer arrival in the rostral CSF space and the nasal cavity with tracer retention in the ventral CSF space were observed in the ligation group. The maximum slopes were smaller in the ligation group at UNT (sham: 0.075 ± 0.0061, ligation: 0.044 ± 0.0086/min, P = 0.011). A significant difference was not detected in peak timings. The peak signal ratio values were lower in the ligation group at UNT (sham: 2.12 ± 0.19, ligation: 1.72 ± 0.11, P = 0.011). The elimination half-life was delayed in the ligation group at CSF_C1 (sham: 30.5 ± 2.70, ligation: 44.4 ± 12.6 min, P = 0.043), CSF_OB (sham: 30.2 ± 2.67, ligation: 44.8 ± 7.47 min, P = 0.021), and CSF_PitR (sham: 30.2 ± 2.49, ligation: 41.3 ± 7.57 min, P = 0.021). CONCLUSION: The DCLN ligation in rats blocked CSF outflow into the nasal cavity and caused CSF retention.
  • Hiroyuki Hamaguchi, Maho Kitagawa, Daiki Sakamoto, Ulrich Katscher, Hideki Sudo, Katsuhisa Yamada, Kohsuke Kudo, Khin Khin Tha
    Tomography (Ann Arbor, Mich.) 9 (3) 1029 - 1040 2023/05/16 
    Whether diurnal variation exists in quantitative MRI indices such as the T1rho relaxation time (T1ρ) of the intervertebral disc (IVD) is yet to be explored. This prospective study aimed to evaluate the diurnal variation in T1ρ, apparent diffusion coefficient (ADC), and electrical conductivity (σ) of lumbar IVD and its relationship with other MRI or clinical indices. Lumbar spine MRI, including T1ρ imaging, diffusion-weighted imaging (DWI), and electric properties tomography (EPT), was conducted on 17 sedentary workers twice (morning and evening) on the same day. The T1ρ, ADC, and σ of IVD were compared between the time points. Their diurnal variation, if any, was tested for correlation with age, body mass index (BMI), IVD level, Pfirrmann grade, scan interval, and diurnal variation in IVD height index. The results showed a significant decrease in T1ρ and ADC and a significant increase in the σ of IVD in the evening. T1ρ variation had a weak correlation with age and scan interval, and ADC variation with scan interval. Diurnal variation exists for the T1ρ, ADC, and σ of lumbar IVD, which should be accounted for in image interpretation. This variation is thought to be due to diurnal variations in intradiscal water, proteoglycan, and sodium ion concentration.
  • Noriko Nishioka, Noriyuki Fujima, Satonori Tsuneta, Masami Yoneyama, Ryuji Matsumoto, Takashige Abe, Rina Kimura, Keita Sakamoto, Fumi Kato, Kohsuke Kudo
    Medicine 102 (17) e33639  2023/04/25 
    We investigated the ability of echo-planar imaging with L1-regularized iterative sensitivity encoding-based diffusion-weighted imaging (DWI) to improve the image quality and reduce the scanning time in prostate magnetic resonance imaging. We retrospectively analyzed 109 cases of prostate magnetic resonance imaging. We compared variables in the quantitative and qualitative assessments among 3 imaging groups: conventional parallel imaging-based DWI (PI-DWI) with an acquisition time of 3 minutes 15 seconds; echo-planar imaging with L1-regularized iterative sensitivity encoding-based DWI (L1-DWI) with a normal acquisition time (L1-DWINEX12) of 3 minutes 15 seconds; and L1-DWI with a half acquisition time (L1-DWINEX6) of 1 minute 45 seconds. As a quantitative assessment, the signal-to-noise ratio (SNR) of DWI (SNR-DWI), the contrast-to-noise ratio (CNR) of DWI (CNR-DWI), and the CNR of apparent diffusion coefficient were measured. As a qualitative assessment, the image quality and visual detectability of prostate carcinoma were evaluated. In the quantitative analysis, L1-DWINEX12 showed significantly higher SNR-DWI than PI-DWI (P = .0058) and L1-DWINEX6 (P < .0001). In the qualitative analysis, the image quality score for L1-DWINEX12 was significantly higher than those of PI-DWI and L1-DWINEX6. A non-inferiority assessment demonstrated that L1-DWINEX6 was non-inferior to PI-DWI in terms of both quantitative CNR-DWI and qualitative grading of image quality with a <20% inferior margin. L1-DWI successfully demonstrated a reduced scanning time while maintaining good image quality.
  • Moto Fukai, Hiroyuki Sugimori, Sodai Sakamoto, Kengo Shibata, Hiroyuki Kameda, Takahisa Ishikawa, Norio Kawamura, Masato Fujiyoshi, Sunao Fujiyoshi, Kohsuke Kudo, Tsuyoshi Shimamura, Akinobu Taketomi
    Transplantation proceedings 55 (4) 1032 - 1035 2023/04/10 
    Interventions for liver grafts with moderate macrovesicular steatosis have been important in enlarging donor pools. Here, we tested a high-fat and cholesterol (HFC) diet to create a steatosis model for cold hepatic preservation and reperfusion experiments. The aim of the present study was to assess the steatosis model's reliability and to show the resulting graft's quality for cold preservation and reperfusion experiment. Male SHRSP5-Dmcr rats were raised with an HFC diet for up to 2 weeks. The fat content was evaluated using magnetic resonance imaging (MRI) proton density fat fraction (PDFF). The nonalcoholic fatty liver disease activity score (NAS) was evaluated after excision. Steatosis created by 2 weeks of HFC diet was subjected to 24-hour cold storage in the University of Wisconsin and the original test solution (new sol.). Grafts were applied to isolated perfused rat livers for simulating reperfusion. The NAS were 2.2 (HFC 5 days), 3.3 (HFC 1 week), and 5.0 (HFC 2 weeks). Ballooning and fibrosis were not observed in any group. An MRI-PDFF showed 0.2 (HFC 0 days), 12.0 (HFC 1 week), and 18.9 (HFC 2 weeks). The NAS and MRI-PDFF values correlated. Many indices in the isolated perfused rat liver experiment tended to improve in the new sol. group but were insufficient. Although the new sol. failed to be effective, it acted at multiple sites under difficult conditions. In conclusion, the HFC diet for 2 weeks in SHRSP5-Dmcr rats, together with MRI-PDFF evaluation, is a reliable method for creating simple steatosis and provides good-quality cold preservation and reperfusion experiments.
  • 腹部手術後門脈狭窄/閉塞に対する門脈ステント留置による血液検査データ変化に関する検討
    木野田 直也, 阿保 大介, 木村 輔, 作原 祐介, 藤井 宝顕, 加藤 大祐, 高橋 文也, 森田 亮, 折茂 達也, 柿坂 達彦, 中村 透, 平野 聡, 箕輪 和行, 工藤 與亮
    日本インターベンショナルラジオロジー学会雑誌 (一社)日本インターベンショナルラジオロジー学会 38 (Suppl.) 205 - 205 1340-4520 2023/04
  • 肝左葉尾状葉切除術後の門脈狭窄、右肝動脈出血に対しstentgraft留置が奏功した一例
    村本 朋之, 阿保 大介, 森田 亮, 高橋 文也, 木野田 直也, 加藤 大祐, 藤井 宝顕, 田中 公貴, 中西 喜嗣, 野路 武寛, 平野 聡, 工藤 與亮
    日本インターベンショナルラジオロジー学会雑誌 (一社)日本インターベンショナルラジオロジー学会 38 (Suppl.) 205 - 205 1340-4520 2023/04
  • 高精細3D血管モデルを用いた術前シミュレーションの有用性(The usefulness of preoperative simulation with 3D-printed patient-specific hollow vascular models)
    森田 亮, 阿保 大介, 曽山 武士, 今井 哲秋, 高橋 文也, 吉野 裕紀, 木野田 直也, 加藤 大祐, 藤井 宝顕, 濱口 裕行, 亀田 拓人, 工藤 與亮
    日本インターベンショナルラジオロジー学会雑誌 38 (Suppl.) 236 - 236 1340-4520 2023/04
  • 4D-flow MRIを用いたportosystemic shunt閉塞前後の門脈血流評価
    加藤 大祐, 阿保 大介, 木野田 直也, 常田 慧徳, 石坂 欣也, 森田 亮, 高橋 文也, 藤井 宝顕, 工藤 與亮
    日本インターベンショナルラジオロジー学会雑誌 (一社)日本インターベンショナルラジオロジー学会 38 (Suppl.) 237 - 237 1340-4520 2023/04
  • 肝エキノコックス症による右肝静脈狭窄に対してcovered stentを留置した一例
    渡辺 祈一, 阿保 大介, 森田 亮, 木野田 直也, 高橋 文也, 加藤 大祐, 藤井 宝顕, 柿坂 達彦, 折茂 達也, 工藤 與亮
    日本インターベンショナルラジオロジー学会雑誌 (一社)日本インターベンショナルラジオロジー学会 38 (Suppl.) 277 - 277 1340-4520 2023/04
  • Tomoka Shima, Noriyuki Fujima, Shigeru Yamano, Hiroyuki Kameda, Masaaki Suzuka, Akiko Takeuchi, Yurika Kinoshita, Nanami Iwai, Kohsuke Kudo, Kazuyuki Minowa
    Oral radiology 39 (4) 661 - 667 2023/03/27 
    OBJECTIVES: To investigate possible associations between diffusion-weighted imaging (DWI) parameters derived from a non-Gaussian model fitting and Ki-67 status in patients with oral squamous cell carcinoma (OSCC). METHODS: Twenty-four patients with newly diagnosed OSCC were prospectively recruited. DWI was performed using six b-values (0-2500). The diffusion-related parameters of kurtosis value (K), kurtosis-corrected diffusion coefficient (DK), diffusion heterogeneity (α), distributed diffusion coefficient (DDC), slow diffusion coefficient (Dslow), and apparent diffusion coefficient (ADC) were calculated from four diffusion fitting models. Ki-67 status was categorized as low (Ki-67 percentage score < 20%), middle (20-50%), or high (> 50%). Kruskal-Wallis tests were performed between each non-Gaussian diffusion model parameters and Ki-67 grade. RESULTS: The Kruskal-Wallis tests revealed that multiple parameters (K, ADC, Dk, DDC and Dslow) showed statistically significant differences between the three levels of Ki-67 status (K: p = 0.020, ADC: p = 0.012, Dk: p = 0.027, DDC: p = 0.007 and Dslow: p = 0.026). CONCLUSIONS: Several non-Gaussian diffusion model parameters and ADC values were significantly associated with Ki-67 status and have potential as promising prognostic biomarkers in patients with OSCC.
  • 胸膜孤立性線維性腫瘍に合併したDoege-potter症候群の一例
    村本 朋之, 中川 純一, 常田 慧徳, 高橋 文也, 木村 理奈, 西岡 典子, 坂本 圭太, 加藤 扶美, 氏家 秀樹, 加藤 達哉, 大藤 悠理, 亀田 啓, 中村 昭伸, 若林 健人, 松野 吉宏, 工藤 與亮
    北海道放射線医学雑誌 (NPO)メディカルイメージラボ 3 28 - 32 2023/03 
    症例は60歳代女性。X-1年の検診で右胸部に異常影を指摘された。X年に胸部異常影増大と空腹時血糖38mg/dLの著明低値を認めたため前医を受診し、CTで右胸腔下部を占拠する巨大腫瘤を認めた。針生検で孤立性線維性腫瘍(solitary fibrous tumor:SFT)が疑われたため、手術目的に当院呼吸器外科に紹介受診となった。入院後低血糖時の採血でinsulinとC-peptideの低下を認めた。腫瘍はMRIではT2強調像で低信号を主体として高信号が混在し、内部にflow voidを認めた。造影後T1強調像では強く増強され、内部に血管が発達していた。腫瘍摘出術が施行され、SFTの確定診断となった。術前に頻発していた低血糖は術直後から消失し、SFTに伴う非膵島細胞腫瘍性低血糖症と考えられた。本病態はDoege-Potter症候群として知られ、SFTの5%以下の症例で生じるとされる。低血糖を合併した軟部腫瘍ではSFTが鑑別のひとつに挙げられる。(著者抄録)
  • Sunburst appearanceを呈する頭蓋骨腫瘤を契機に発見された神経芽腫の1例
    北川 悠, 竹中 淳規, 渡邊 史郎, 平田 健司, 内山 裕子, 木村 理奈, 中川 純一, 池辺 洋平, 長谷河 昌孝, 澤井 彩織, 寺下 友佳代, 杉山 未奈子, 平林 真介, 長 祐子, 山口 秀, 真部 淳, 工藤 與亮
    北海道放射線医学雑誌 (NPO)メディカルイメージラボ 3 33 - 36 2023/03 
    症例は9歳女児。左頭部腫瘤を主訴に近医を受診し、頭部CTで左前頭骨にsunburst appearanceを呈する腫瘤性病変を指摘され、その他にも右頭頂骨と左下顎頭に骨病変を認めた。体幹部造影CTを施行したところ、後縦隔の胸椎椎体前方から左側にかけて巨大な軟部腫瘤を認めた。血清神経特異エノラーゼ(NSE)や尿中バニリルマンデル酸(VMA)/ホモバニリン酸(HVA)が高値であり、神経芽腫が第一に疑われた。123I-MIBGシンチグラフィを施行したところ、後縦隔腫瘤のほか頭蓋骨を含めた全身骨にも集積が見られ、神経芽腫とその骨転移が疑われた。頭蓋骨腫瘤の生検術により神経芽腫の診断が確定した。神経芽腫は小児期に発生する頭蓋外の固形悪性腫瘍の中で最も頻度が高い。転移性頭蓋骨腫瘍がsunburst appearanceを呈することは比較的稀であるが、小児では神経芽腫の転移でしばしば経験される。神経芽腫の骨転移の部位として、頭蓋骨は頻度が高く、小児においてsunburst appearanceを呈し多発する頭蓋骨腫瘤を見た場合には神経芽腫の骨転移を考慮する必要がある。(著者抄録)
  • Hiroyuki Uetani, Minako Azuma, Zaw Aung Khant, Yoshiyuki Watanabe, Kohsuke Kudo, Yoshihito Kadota, Kiyotaka Yokogami, Hideo Takeshima, Jun-Ichiro Kuroda, Naoki Shinojima, Tadashi Hamasaki, Akitake Mukasa, Toshinori Hirai
    Journal of computer assisted tomography 2023/02/10 
    PURPOSE: This study aimed to investigate the most useful clinical and magnetic resonance imaging (MRI) parameters for differentiating isocitrate dehydrogenase (IDH)-mutant and -wildtype glioblastomas in the 2016 World Health Organization Classification of Tumors of the Central Nervous System. METHODS: This multicenter study included 327 patients with IDH-mutant or IDH-wildtype glioblastoma in the 2016 World Health Organization classification who preoperatively underwent MRI. Isocitrate dehydrogenase mutation status was determined by immunohistochemistry, high-resolution melting analysis, and/or IDH1/2 sequencing. Three radiologists independently reviewed the tumor location, tumor contrast enhancement, noncontrast-enhancing tumor (nCET), and peritumoral edema. Two radiologists independently measured the maximum tumor size and mean and minimum apparent diffusion coefficients of the tumor. Univariate and multivariate logistic regression analyses with an odds ratio (OR) were performed. RESULTS: The tumors were IDH-wildtype glioblastoma in 306 cases and IDH-mutant glioblastoma in 21. Interobserver agreement for both qualitative and quantitative evaluations was moderate to excellent. The univariate analyses revealed a significant difference in age, seizure, tumor contrast enhancement, and nCET (P < 0.05). The multivariate analysis revealed significant difference in age for all 3 readers (reader 1, odds ratio [OR] = 0.960, P = 0.012; reader 2, OR = 0.966, P = 0.048; reader 3, OR = 0.964, P = 0.026) and nCET for 2 readers (reader 1, OR = 3.082, P = 0.080; reader 2, OR = 4.500, P = 0.003; reader 3, OR = 3.078, P = 0.022). CONCLUSIONS: Age and nCET are the most useful parameters among the clinical and MRI parameters for differentiating IDH-mutant and IDH-wildtype glioblastomas.
  • Ryo Morita, Takayuki Nonoyama, Daisuke Abo, Takeshi Soyama, Fujima Noriyuki, Tetsuaki Imai, Hiroyuki Hamaguchi, Takuto Kameda, Osamu Sugita, Bunya Takahashi, Naoya Kinota, Kohsuke Kudo
    Journal of vascular and interventional radiology : JVIR 34 (5) 871 - 878 2023/01/13 [Refereed]
     
    PURPOSE: To develop a vascular intervention simulation model that replicates the characteristics of a human patient, the mechanical properties of a three-dimensional (3D)- printed transparent flexible resin were compared with those of porcine arteries using the elastic modulus (E) and kinetic friction coefficient (μ_k). MATERIALS AND METHODS: Resin plates were created from transparent flexible resin using a 3D printer. Porcine artery plates were prepared by excising the aorta. E, adhesive strength of resin and arterial surface toward polyethylene plate, was measured with a tensile-compressive mechanical tester. The resin transparency was measured with an ultraviolet-visible light spectrometer. μ_k of the resin plate surface after applying silicone spray for 1-5 s and that of the artery were measured with a translational friction tester. RESULTS: E differed significantly between the arteries and resin plates at each curing time (0.20 ±0.04 vs. 8.53 ±2.37 MPa for a curing time of 1 min, P<0.05). The resin was stiffer than the arteries, regardless of the curing times. The visible light transmittance and adhesive strength of the resin decreased as the curing time increased. The adhesive strength of the artery was the lowest. μ_k of the silicone-coated resin surface created by applying silicone for 2-3 s (thickness of the silicone layer: 1.6-2 μm) was comparable with that of the artery, indicating that the coating imparted a similar slippage to the resin as the living artery. CONCLUSION: Transparent flexible resin is useful for creating a transparent and slippery vascular model for vascular intervention simulation.
  • Hikaru Hagiwara, Masaya Watanabe, Takahide Kadosaka, Takuya Koizumi, Yuta Kobayashi, Taro Koya, Motoki Nakao, Satonori Tsuneta, Yoshiya Kato, Hirokazu Komoriyama, Rui Kamada, Toshiyuki Nagai, Kohsuke Kudo, Toshihisa Anzai
    Heart and vessels 2023/01/13 
    Fragmented QRS (fQRS) on a 12-lead electrocardiogram is a known marker of fatal arrhythmias or cardiac adverse events in ischemic and non-ischemic cardiomyopathy patients. Nonetheless, the association between fQRS and clinical outcomes in patients with cardiac sarcoidosis (CS) remains unclear. Herein, we investigated whether fQRS is associated with long-term clinical outcomes in CS patients. A total of 78 patients who received immunosuppressive therapy (IST) for clinically diagnosed CS were retrospectively examined. Patients were classified into two groups according to the presence (n = 19) or absence (n = 59) of fQRS on electrocardiogram before IST. The primary outcome was the composite event of all-cause death, ventricular tachyarrhythmias (VTs), and hospitalization for heart failure. Results of late gadolinium enhancement on cardiac magnetic resonance imaging were also analyzed. During a median follow-up period of 3.7 years (interquartile range: 1.6-6.2 years), the primary outcome occurred more frequently in patients with fQRS than in those without (47% vs. 13%, log-rank p = 0.002). Multivariable Cox regression analyses showed that fQRS was an independent determinant of the primary outcome. The incidence of VTs, within 12 months of IST initiation, was comparable between the two groups; however, late-onset VTs, defined as those occurring ≥ 12 months after IST initiation, occurred more frequently in the fQRS group (21% vs. 2%, log-rank p = 0.002). The scar zone and scar border zone were greater in patients with fQRS than in those without it. In conclusion, our analysis suggests that fQRS is an independent predictor of adverse events, particularly late-onset VTs, in patients with CS.
  • MIP類似アルゴリズムによるFDG-PET体表画像の有用性
    平田 健司, 木村 理奈, 唐 明輝, 渡邊 史郎, 竹中 淳規, 若林 直人, 杉森 博行, 吉村 高明, 工藤 與亮
    核医学 (一社)日本核医学会 60 (Suppl.) S208 - S208 0022-7854 2023
  • SRCNNを用いた短時間収集PET画像の画質改善モデルの開発と定量性評価
    遠藤 大輝, 吉村 高明, 唐 明輝, 杉森 博行, 長谷川 淳, 小亀 翔揮, 孫田 惠一, 木村 理奈, 渡邊 史郎, 平田 健司, 工藤 與亮
    核医学 (一社)日本核医学会 60 (Suppl.) S209 - S209 0022-7854 2023
  • 切除不能/転移性PPGLにおける初回I-131MIBG治療による総糖代謝量の変化と予後の関係性の解析
    竹中 淳規, 渡邊 史郎, 安部 崇重, 土川 貴裕, 竹内 啓, 平田 健司, 木村 理奈, 若林 直人, 篠原 信雄, 工藤 與亮
    核医学 (一社)日本核医学会 60 (Suppl.) S216 - S216 0022-7854 2023
  • 褐色細胞腫・傍神経節腫に対するI-131MIBG治療の単回投与と複数回投与での有害事象発生率の検討
    若林 直人, 渡邊 史郎, 安部 崇重, 竹中 淳規, 平田 健司, 篠原 信雄, 工藤 與亮
    核医学 (一社)日本核医学会 60 (Suppl.) S216 - S216 0022-7854 2023
  • Junki Takenaka, Kenji Hirata, Shiro Watanabe, Hideaki Shiraishi, Kohsuke Kudo
    Asia Oceania journal of nuclear medicine & biology 11 (1) 93 - 96 2023 
    A 2-year-old girl started to wobble without any specific triggers, so the patient was admitted to our hospital's pediatric department. The entire cerebellum showed severe atrophy on MRI and much lower uptake than that in the cerebral cortex on perfusion SPECT. The diagnosis of opsoclonus-myoclonus syndrome (OMS) was suspected. MRI visualized a small mass behind the inferior vena cava. Although its uptake on I-123 MIBG scintigraphy was inconclusive, the mass was surgically removed, and the diagnosis of neuroblastoma was pathologically confirmed. OMS is one of the paraneoplastic neurological syndromes with cerebellar ataxia, myoclonus of the trunk and extremities, and opsoclonus as its main symptoms. Approximately 50% of children cases with OMS are associated with neuroblastoma. The prognosis for neuroblastoma itself with OMS is relatively good, but the neurological prognosis is very poor. If there is decreased blood flow in the cerebellum of an infant, it may be necessary to search for neuroblastoma.
  • MIP類似アルゴリズムによるFDG-PET体表画像の有用性
    平田 健司, 木村 理奈, 唐 明輝, 渡邊 史郎, 竹中 淳規, 若林 直人, 杉森 博行, 吉村 高明, 工藤 與亮
    核医学 (一社)日本核医学会 60 (Suppl.) S208 - S208 0022-7854 2023
  • SRCNNを用いた短時間収集PET画像の画質改善モデルの開発と定量性評価
    遠藤 大輝, 吉村 高明, 唐 明輝, 杉森 博行, 長谷川 淳, 小亀 翔揮, 孫田 惠一, 木村 理奈, 渡邊 史郎, 平田 健司, 工藤 與亮
    核医学 (一社)日本核医学会 60 (Suppl.) S209 - S209 0022-7854 2023
  • Tsubasa Kunieda, Ren Togo, Noriko Nishioka, Yukie Shimizu, Shiro Watanabe, Kenji Hirata, Keisuke Maeda, Takahiro Ogawa 0001, Kohsuke Kudo, Miki Haseyama
    ICCE-Taiwan 165 - 166 2023
  • Takaaki Yoshimura, Kentaro Nishioka, Takayuki Hashimoto, Takashi Mori, Shoki Kogame, Kazuya Seki, Hiroyuki Sugimori, Hiroko Yamashina, Yusuke Nomura, Fumi Kato, Kohsuke Kudo, Shinichi Shimizu, Hidefumi Aoyama
    PloS one 18 (1) e0280076  2023 
    In urethra-sparing radiation therapy, prostatic urinary tract visualization is important in decreasing the urinary side effect. A methodology has been developed to visualize the prostatic urinary tract using post-urination magnetic resonance imaging (PU-MRI) without a urethral catheter. This study investigated whether the combination of PU-MRI and super-resolution (SR) deep learning models improves the visibility of the prostatic urinary tract. We enrolled 30 patients who had previously undergone real-time-image-gated spot scanning proton therapy by insertion of fiducial markers. PU-MRI was performed using a non-contrast high-resolution two-dimensional T2-weighted turbo spin-echo imaging sequence. Four different SR deep learning models were used: the enhanced deep SR network (EDSR), widely activated SR network (WDSR), SR generative adversarial network (SRGAN), and residual dense network (RDN). The complex wavelet structural similarity index measure (CW-SSIM) was used to quantitatively assess the performance of the proposed SR images compared to PU-MRI. Two radiation oncologists used a 1-to-5 scale to subjectively evaluate the visibility of the prostatic urinary tract. Cohen's weighted kappa (k) was used as a measure of agreement of inter-operator reliability. The mean CW-SSIM in EDSR, WDSR, SRGAN, and RDN was 99.86%, 99.89%, 99.30%, and 99.67%, respectively. The mean prostatic urinary tract visibility scores of the radiation oncologists were 3.70 and 3.53 for PU-MRI (k = 0.93), 3.67 and 2.70 for EDSR (k = 0.89), 3.70 and 2.73 for WDSR (k = 0.88), 3.67 and 2.73 for SRGAN (k = 0.88), and 4.37 and 3.73 for RDN (k = 0.93), respectively. The results suggest that SR images using RDN are similar to the original images, and the SR deep learning models subjectively improve the visibility of the prostatic urinary tract.
  • Feng Han, ZiHeng Zhang, Hongjian Zhang, Jun Nakaya, Kohsuke Kudo, Katsuhiko Ogasawara
    JMIR formative research 6 (11) e38677  2022/11/18 
    BACKGROUND: Due to the development of medical data, a large amount of clinical data has been generated. These unstructured data contain substantial information. Extracting useful knowledge from this data and making scientific decisions for diagnosing and treating diseases have become increasingly necessary. Unstructured data, such as in the Marketplace for Medical Information in Intensive Care III (MIMIC-III) data set, contain several ambiguous words that demonstrate the subjectivity of doctors, such as descriptions of patient symptoms. These data could be used to further improve the accuracy of medical diagnostic system assessments. To the best of our knowledge, there is currently no method for extracting subjective words that express the extent of these symptoms (hereinafter, "degree words"). OBJECTIVE: Therefore, we propose using the fuzzy c-means (FCM) method and Gaussian membership to quantify the degree words in the clinical medical data set MIMIC-III. METHODS: First, we preprocessed the 381,091 radiology reports collected in MIMIC-III, and then we used the FCM method to extract degree words from unstructured text. Thereafter, we used the Gaussian membership method to quantify the extracted degree words, which transform the fuzzy words extracted from the medical text into computer-recognizable numbers. RESULTS: The results showed that the digitization of ambiguous words in medical texts is feasible. The words representing each degree of each disease had a range of corresponding values. Examples of membership medians were 2.971 (atelectasis), 3.121 (pneumonia), 2.899 (pneumothorax), 3.051 (pulmonary edema), and 2.435 (pulmonary embolus). Additionally, all extracted words contained the same subjective words (low, high, etc), which allows for an objective evaluation method. Furthermore, we will verify the specific impact of the quantification results of ambiguous words such as symptom words and degree words on the use of medical texts in subsequent studies. These same ambiguous words may be used as a new set of feature values to represent the disorders. CONCLUSIONS: This study proposes an innovative method for handling subjective words. We used the FCM method to extract the subjective degree words in the English-interpreted report of the MIMIC-III and then used the Gaussian functions to quantify the subjective degree words. In this method, words containing subjectivity in unstructured texts can be automatically processed and transformed into numerical ranges by digital processing. It was concluded that the digitization of ambiguous words in medical texts is feasible.
  • Atsushi Tada, Toshiyuki Nagai, Yoshiya Kato, Kazunori Omote, Noriko Oyama-Manabe, Satonori Tsuneta, Yusuke Kudo, Mutsumi Nishida, Michikazu Nakai, Yuki Takahashi, Kohei Saiin, Seiichiro Naito, Yuta Kobayashi, Sakae Takenaka, Yoshifumi Mizuguchi, Kiwamu Kamiya, Takao Konishi, Takuma Sato, Kohsuke Kudo, Toshihisa Anzai
    European radiology 33 (3) 2062 - 2074 2022/11/03 
    OBJECTIVES: Evaluation of liver stiffness (LS) by magnetic resonance elastography (MRE) is useful for estimating right atrial pressure (RAP) in patients with heart failure (HF). However, its prognostic implications are unclear. We sought to investigate whether LS measured by MRE (LS-MRE) could predict clinical outcomes in patients with HF. METHODS: We prospectively examined 207 consecutive HF patients between April 2018 and May 2021 after excluding those with organic liver disease. All patients underwent 3.0-T MRE. The primary outcome of interest was the composite of all-cause death and hospitalisation for HF. RESULTS: During a median follow-up period of 720 (interquartile range [IQR] 434-1013) days, the primary outcome occurred in 44 patients (21%), including 15 (7%) all-cause deaths and 29 (14%) hospitalisations for HF. The patients were divided into two groups according to median LS-MRE of 2.54 (IQR 2.34-2.82) kPa. Patients with higher LS-MRE showed a higher incidence of the primary outcome compared to those with lower LS-MRE (p < 0.001). Multivariable Cox regression analyses revealed that LS-MRE value was independently associated with the risk of adverse events (hazard ratio 2.49, 95% confidence interval 1.46-4.24). In multivariable linear regression, RAP showed a stronger correlation with LS-MRE (β coefficient = 0.31, p < 0.001) compared to markers related to liver fibrosis. CONCLUSIONS: In patients without chronic liver disease and presenting with HF, elevated LS-MRE was independently associated with worse clinical outcomes. Elevated LS-MRE may be useful for risk stratification in patients with HF and without chronic liver disease. KEY POINTS: • Magnetic resonance elastography (MRE) is an emerging non-invasive imaging technique for evaluating liver stiffness (LS) which can estimate right atrial pressure. • Elevated LS-MRE, which mainly reflects liver congestion, was independently associated with worse clinical outcomes in patients with heart failure. • The assessment of LS-MRE would be useful for stratifying the risk of adverse events in heart failure patients without chronic liver disease.
  • Junki Takenaka, Shiro Watanabe, Takashige Abe, Kenji Hirata, Yuko Uchiyama, Rina Kimura, Nobuo Shinohara, Kohsuke Kudo
    Annals of nuclear medicine 2022/10/27 
    OBJECTIVE: Pheochromocytomas and paragangliomas (PPGLs) are rare tumors arising from the neural crest cells that form the sympathetic and parasympathetic nervous systems. Radiotherapy with [131I]metaiodobenzylguanidine (MIBG) is recommended for unresectable PPGLs. We investigated the usefulness of the metabolic tumor volume (MTV) and total lesion glycolysis (TLG) derived from [18F]fluorodeoxyglucose-positron emission tomography (FDG-PET) for predicting the prognosis of patients with unresectable PPGL(s) before receiving [131I]MIBG therapy. PATIENTS AND METHODS: We retrospectively analyzed the cases of 25 patients with unresectable PPGLs treated with [131I]MIBG at our hospital between 2001 and 2020. The MTV and TLG were measured in reference to liver accumulation. We divided the patients into two groups based on median values for the maximum standardized uptake value (SUVmax), MTV, and TLG, and evaluated between-group differences using log-rank tests. Cox proportional hazards models were used to determine whether there were significant differences in prognosis with respect to tumor type (pheochromocytoma vs. paraganglioma), site of metastasis, age, past treatment (chemotherapy, external radiation or [131I]MIBG treatment before the current [131I]MIBG treatment), urinary catecholamine, SUVmax, MTV, and TLG. RESULTS: The median follow-up time was 42 months (range 2-136 months). The median overall survival was 63 months. The overall survival (OS) was significantly shorter in the high-MTV group (log-rank test, p = 0.049) and the high-TLG group (p = 0.049), with no significant difference between the high- and low-SUVmax groups (p = 0.19). Likewise, there was no significant difference in prognosis according to pheochromocytoma or paraganglioma, metastasis location, age, or prior chemotherapy. A history of external radiation before [131I]MIBG treatment was associated with a significantly worse prognosis (hazard ration [HR] = 7.95, p = 0.0018). Urinary adrenaline and noradrenaline were not significant prognostic factors (p = 0.70, p = 0.25, respectively), but urinary dopamine did predict a worse outcome (p = 0.022). There was no increased risk of death for higher SUVmax or TLG (p = 0.63 and 0.057, respectively), but higher MTV did predict a worse outcome (HR = 7.27, p = 0.029). CONCLUSION: High MTV and high TLG were significantly associated with a poor prognosis after [131I]MIBG therapy for PPGLs. Other treatment strategies for such patients may need to be explored.
  • 渡辺 祈一, 池辺 洋平, 工藤 與亮
    日本医事新報 (株)日本医事新報社 (5139) 1 - 2 0385-9215 2022/10
  • Ryo Morita, Daisuke Abo, Taisuke Harada, Takeshi Soyama, Bunya Takahashi, Yuki Yoshino, Naoya Kinota, Taichi Yasui, Kohsuke Kudo
    Radiographics : a review publication of the Radiological Society of North America, Inc 42 (6) E171-E172  2022/10
  • Ryo Morita, Daisuke Abo, Takeshi Soyama, Tetsuaki Imai, Bunya Takahashi, Yuki Yoshino, Naoya Kinota, Hiroyuki Hamaguchi, Takuto Kameda, Kohsuke Kudo
    Radiology case reports 17 (10) 3578 - 3586 2022/10 
    The development of three-dimensional printers has facilitated the creation of patient-specific hollow vessel models. Preoperative simulations using these types of models have improved our ability to select appropriate devices and embolic materials before performing complex endovascular procedures. This report describes 2 cases of high-flow renal arteriovenous fistulas (r-AVFs) that were successfully treated via short-segment embolization using the preloading coil-in-plug (p-CIP) technique. To our knowledge, this is the first report of r-AVF being treated using the p-CIP technique. Our findings demonstrate that preoperative simulation has the potential to improve the safety and reliability of complex vascular embolization procedures.
  • Junichi Nakagawa, Noriyuki Fujima, Kenji Hirata, Minghui Tang, Satonori Tsuneta, Jun Suzuki, Taisuke Harada, Yohei Ikebe, Akihiro Homma, Satoshi Kano, Kazuyuki Minowa, Kohsuke Kudo
    Cancer imaging : the official publication of the International Cancer Imaging Society 22 (1) 52 - 52 2022/09/22 
    BACKGROUND: In nasal or sinonasal tumors, orbital invasion beyond periorbita by the tumor is one of the important criteria in the selection of the surgical procedure. We investigated the usefulness of the convolutional neural network (CNN)-based deep learning technique for the diagnosis of orbital invasion, using computed tomography (CT) images. METHODS: A total of 168 lesions with malignant nasal or sinonasal tumors were divided into a training dataset (n = 119) and a test dataset (n = 49). The final diagnosis (invasion-positive or -negative) was determined by experienced radiologists who carefully reviewed all of the CT images. In a CNN-based deep learning analysis, a slice of the square target region that included the orbital bone wall was extracted and fed into a deep-learning training session to create a diagnostic model using transfer learning with the Visual Geometry Group 16 (VGG16) model. The test dataset was subsequently tested in CNN-based diagnostic models and by two other radiologists who were not specialized in head and neck radiology. At approx. 2 months after the first reading session, two radiologists again reviewed all of the images in the test dataset, referring to the diagnoses provided by the trained CNN-based diagnostic model. RESULTS: The diagnostic accuracy was 0.92 by the CNN-based diagnostic models, whereas the diagnostic accuracies by the two radiologists at the first reading session were 0.49 and 0.45, respectively. In the second reading session by two radiologists (diagnosing with the assistance by the CNN-based diagnostic model), marked elevations of the diagnostic accuracy were observed (0.94 and 1.00, respectively). CONCLUSION: The CNN-based deep learning technique can be a useful support tool in assessing the presence of orbital invasion on CT images, especially for non-specialized radiologists.
  • Shigeru Yamaguchi, Michinari Okamoto, Yukitomo Ishi, Ryosuke Sawaya, Hiroaki Motegi, Minako Sugiyama, Taisuke Harada, Noriyuki Fujima, Takashi Mori, Takayuki Hashimoto, Emi Takakuwa, Atsushi Manabe, Kohsuke Kudo, Hidefumi Aoyama, Miki Fujimura
    Journal of neurosurgery. Pediatrics 1 - 8 2022/09/09 
    OBJECTIVE: In patients with intracranial germ cell tumors, residual lesions are sometimes observed after completion of primary chemoradiotherapy. Although salvage resection of these end-of-treatment residual lesions is recommended for patients with nongerminomatous germ cell tumors, the necessity of early salvage resection for those with germinoma is not clear. The aim of this study was to investigate the frequency of residual germinoma lesions after primary chemoradiotherapy, as well as their management, long-term consequences, and prognosis. METHODS: The authors retrospectively reviewed patients who were primarily treated for germinoma between 2002 and 2021. Residual lesions were evaluated with MRI with and without contrast enhancement within 2 weeks after chemoradiotherapy. The decision to perform salvage resection of residual lesions was at the discretion of the treating physicians. The change in appearance of residual lesions was assessed with serial MRI. Overall survival (OS), progression-free survival (PFS), and recurrence pattern were also investigated. RESULTS: Sixty-nine patients were treated with chemoradiotherapy for germinoma, with a mean follow-up period of 108 months. Residual lesions were radiologically observed in 30 patients (43.5%). Among these, 5 patients (3 with pineal lesions and 2 with basal ganglia lesions) underwent salvage resection. Pathological examination revealed teratomatous components in 3 patients, whereas no tumoral components were identified in 2 patients. One patient with a basal ganglia lesion showed worsening of hemiparesis postoperatively. The remaining 25 patients received watchful observation without surgical intervention. Chronological periodic radiological change in residual lesions was evaluated in 21 patients. One year after primary treatment, the size of the residual lesions was stable and had decreased in 10 and 11 patients, respectively. None of the lesions increased in size. The 10-year PFS and OS rates were 96.7% and 97.3% in patients without residual lesions (n = 39), and 87.1% and 100% in patients with residual lesions (n = 30), respectively. Presence of residual lesions had no significant effect on PFS or OS. All recurrences occurred at distant sites or via dissemination without progression of the primary tumor site, regardless of the presence of residual lesion. CONCLUSIONS: End-of-treatment residual lesions are not rare in patients with germinoma, and these residual lesions seldom show progression. Because of the potential risk of surgical complications, the indication for early salvage surgery for residual lesions should be carefully determined. Watchful observation is recommended for the majority of these cases.
  • Haruki Narita, Junki Takenaka, Shiro Watanabe, Takashige Abe, Kohsuke Kudo
    Clinical nuclear medicine 47 (9) e591-e593  2022/09/01 
    A 49-year-old Japanese man had a chief complaint of left hypochondrium pain, and a CT scan revealed a mass in the left retroperitoneal space. CT and MRI scans revealed a hemorrhagic component and surrounding fibrous tissues. FDG PET/CT images showed increased uptake in the peripheral rim of the mass, indicating a malignant tumor. The SUV max was 7.6. We surgically resected the mass. The pathological examination confirmed the diagnosis of chronic expanding hematoma. It is difficult to differentiate CEH from malignant tumors on imaging; this should be recognized as a diagnostic pitfall.
  • AIによる肝臓セグメンテーションの性能評価と肝臓体積の経時的変化
    木村 理奈, 平田 健司, 常田 慧徳, 竹中 淳規, 渡邊 史郎, 阿保 大介, 工藤 與亮
    日本医学放射線学会秋季臨床大会抄録集 (公社)日本医学放射線学会 59回 S403 - S403 0048-0428 2022/09
  • 日本人肥満2型糖尿病における腹腔鏡下スリーブ状胃切除術が脂肪肝と膵β細胞機能に及ぼす効果 前向きコホート研究
    大江 悠希, 中村 昭伸, 曹 圭龍, 高瀬 崇宏, 小川 浩司, 海老原 裕磨, 吉川 仁人, 西田 睦, 宮 愛香, 野本 博司, 亀田 啓, 荘 拓也, 須田 剛生, 倉島 庸, 阿保 大介, 工藤 與亮, 坂本 直哉, 平野 聡, 渥美 達也, 三好 秀明
    糖尿病合併症 (一社)日本糖尿病合併症学会 36 (Suppl.1) 172 - 172 2022/09
  • Shiro Watanabe, Shozo Okamoto, Kazumasa Akikawa, Noriyuki Miyamoto, Miyuki Okamura-Kawasaki, Yuko Uchiyama, Junki Takenaka, Takuya Toyonaga, Kenji Hirata, Kohsuke Kudo
    Annals of nuclear medicine 2022/08/16 
    OBJECTIVE: Radioactive iodine (RAI) therapy is a useful treatment for Graves' disease (GD). Most RAI sessions administer ≤ 500 MBq of iodine (I)-131. Sometimes patients require repeated RAI, often for longer periods of remission. We investigated the characteristics of patients for whom high dose (mostly 1110 MBq of I-131) RAI was effective as RAI therapy for GD. METHODS: We retrospectively analyzed the cases of 79 patients who underwent RAI for GD in a multicenter setting. We divided the patients into two groups based on the I-131 dose administered: the low dose (LD) group who received ≤ 500 MBq (n = 44) and the high dose (HD) group who received > 500 MBq (n = 35). The therapeutic effect was defined as achieving remission and reaching the point of participating in thyroid hormone replacement therapy within 1 year after RAI. We compared the LD and HD groups' remission rates and conducted a multivariate logistic regression analysis of predictive factors for remission. In a simulation, using the formula for predicting the probability of remission obtained from the analysis results, we estimated how much the remission rate would change if the I-131 dose is increased from 500 to 1110 MBq. RESULTS: The mean ± standard deviation I-131 dose administered in the LD group was 480 ± 6 MBq, and that of the HD group was 1054 ± 265 MBq. Thirty-five patients (80%) in the LD group and 26 patients (74%) in the HD group achieved remission; this difference in the remission rate was not significant. The multivariate analysis results demonstrated that the absorbed dose and thyroid-stimulating antibody (TSAb) were independent predictors of remission. Seven patients (8.9%) showed an increased probability of remission from < 50% to > 50% when the higher RAI dose was applied (1110 MBq instead of 500 MBq). The thyroid volume and TSAb values in these patients were relatively large at 54.7 ± 34.2 mL and 1378.4 ± 586.3%, respectively. CONCLUSION: Although the overall remission rate was not significantly different between the patients who received high- or low-dose I-131, treatment with high-dose RAI may improve the probability of remission in patients with a massive thyroid volume and/or high-TSAb Graves' disease.
  • バセドウ病に対するHigh dose I-131治療による治療効果の改善
    渡邊 史郎, 岡本 祥三, 秋川 和聖, 内山 裕子, 竹中 淳規, 平田 健司, 工藤 與亮
    核医学 (一社)日本核医学会 59 (Suppl.) S463 - S463 0022-7854 2022/08
  • 核医学~近未来核医学の向かう道-診断・治療の精度をあげる最新手法~ 核医学におけるAIの活用と課題
    平田 健司, 杉森 博行, 藤間 憲幸, 豊永 拓哉, 工藤 與亮
    日本医学放射線学会秋季臨床大会抄録集 (公社)日本医学放射線学会 58回 S344 - S344 0048-0428 2022/08
  • 核医学〜近未来核医学の向かう道-診断・治療の精度をあげる最新手法〜 核医学におけるAIの活用と課題
    平田 健司, 杉森 博行, 藤間 憲幸, 豊永 拓哉, 工藤 與亮
    日本医学放射線学会秋季臨床大会抄録集 (公社)日本医学放射線学会 58回 S344 - S344 0048-0428 2022/08
  • Noriyuki Fujima, Yukie Shimizu, Masami Yoneyama, Junichi Nakagawa, Hiroyuki Kameda, Taisuke Harada, Seijiro Hamada, Takayoshi Suzuki, Nayuta Tsushima, Satoshi Kano, Akihiro Homma, Kohsuke Kudo
    Quantitative imaging in medicine and surgery 12 (8) 4024 - 4032 2022/08 
    Background: In head and neck cancers, histopathological information is important for the determination of the tumor characteristics and for predicting the prognosis. The aim of this study was to assess the utility of diffusion-weighted T2 (DW-T2) mapping for the evaluation of tumor histological grade in patients with head and neck squamous cell carcinoma (SCC). Methods: The cases of 41 patients with head and neck SCC (21 well/moderately and 17 poorly differentiated SCC) were retrospectively analyzed. All patients received MR scanning using a 3-Tesla MR unit. The conventional T2 value, DW-T2 value, ratio of DW-T2 value to conventional T2 value, and apparent diffusion coefficient (ADC) were calculated using signal information from the DW-T2 mapping sequence with a manually placed region of interest (ROI). Results: ADC values in the poorly differentiated SCC group were significantly lower than those in the moderately/well differentiated SCC group (P<0.05). The ratio of DW-T2 value to conventional T2 value was also significantly different between poorly and moderately/well differentiated SCC groups (P<0.01). Receiver operating characteristic (ROC) curve analysis of ADC values showed a sensitivity of 0.76, specificity of 0.67, positive predictive value (PPV) of 0.62, negative predictive value (NPV) of 0.8, accuracy of 0.71 and area under the curve (AUC) of 0.73, whereas the ROC curve analysis of the ratio of DW-T2 value to conventional T2 value showed a sensitivity of 0.76, specificity of 0.83, PPV of 0.76, NPV of 0.83, accuracy of 0.8 and AUC of 0.82. Conclusions: DW-T2 mapping might be useful as supportive information for the determination of tumor histological grade in patients with head and neck SCC.
  • Moyoko Tomiyasu, Yasuka Sahara, Etsuko Mitsui, Hiroki Tsuchiya, Takamasa Maeda, Nobuhiro Tomoyori, Makoto Kawashima, Toshifumi Nogawa, Riwa Kishimoto, Yuhei Takado, Tatsuya Higashi, Atsushi Mizota, Kohsuke Kudo, Takayuki Obata
    Journal of magnetic resonance imaging : JMRI 57 (3) 845 - 853 2022/07/15 
    BACKGROUND: Visualization of aqueous humor flow in MR contrast images using gadolinium is challenging because of the delayed contrast effects associated with the blood-retinal and blood-aqueous humor barriers. However, oxygen-17 water (H2 17 O) might be used as an ocular contrast agent. PURPOSE: To observe the distribution of H2 17 O in the human eye, and its flow in and out of the anterior chamber, using dynamic T2-weighted MRI. STUDY TYPE: Prospective. POPULATION: Six ophthalmologically normal volunteers (20-37 years, six females). FIELD STRENGTH/SEQUENCE: A 3 T/dynamic T2-weighted MRI. ASSESSMENT: H2 17 O eye drops were administered to the right eye. Time-series images were created by subtracting the image before the eye drops from each of the images obtained after the eye drops. The normalized signal intensity of the right anterior chamber (nAC) was obtained by dividing the signal intensity of the right anterior chamber region by that of the left. The inflow and outflow constants of H2 17 O and H2 17 O concentration were calculated from the nAC. STATISTICAL TESTS: A paired t-test was used to compare the flow-related values and temporal changes in signal intensity. P-values < 0.05 were considered statistically significant. RESULTS: Significantly decreased signal intensity was observed in the right anterior chamber but not the right vitreous body (P = 0.39). The nAC signal intensity decreased significantly and then recovered. The inflow and outflow constants were 0.36-0.94 min-1 and 0.023-0.13 min-1 , respectively. The maximum H2 17 O concentration was 0.078%-0.24%. DATA CONCLUSION: H2 17 O were distributed in the anterior chamber. The H2 17 O inflow into the anterior chamber was significantly faster than that of the outflow. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY STAGE: 2.
  • Noriyuki Fujima, Yukie Shimizu, Masami Yoneyama, Junichi Nakagawa, Hiroyuki Kameda, Taisuke Harada, Seijiro Hamada, Takayoshi Suzuki, Nayuta Tsushima, Satoshi Kano, Akihiro Homma, Kohsuke Kudo
    Medicine 101 (28) e29457  2022/07/15 
    The aim of this study was to investigate the utility of amide proton transfer (APT) imaging for the determination of human papillomavirus (HPV) status in patients with oropharyngeal squamous cell carcinoma (SCC). Thirty-one patients with oropharyngeal SCC were retrospectively evaluated. All patients underwent amide proton transfer imaging using a 3T magnetic resonance (MR) unit. Patients were divided into HPV-positive and -negative groups depending on the pathological findings in their primary tumor. In APT imaging, the primary tumor was delineated with a polygonal region of interest (ROI). Signal information in the ROI was used to calculate the mean, standard deviation (SD) and coefficient of variant (CV) of the APT signals (APT mean, APT SD, and APT CV, respectively). The value of APT CV in the HPV-positive group (0.43 ± 0.04) was significantly lower than that in the HPV-negative group (0.48 ± 0.04) (P = .01). There was no significant difference in APT mean (P = .82) or APT SD (P = .13) between the HPV-positive and -negative groups. Receiver operating characteristic (ROC) curve analysis of APT CV had a sensitivity of 0.75, specificity of 0.8, positive predictive value of 0.75, negative predictive value of 0.8, accuracy of 0.77 and area under the curve (AUC) of 0.8. The APT signal in the HPV-negative group was considered heterogeneous compared to the HPV-positive group. This information might be useful for the determination of HPV status in patients with oropharyngeal SCC.
  • 平田 健司, 竹中 淳規, 山口 秀, 志賀 哲, 豊永 拓哉, 工藤 與亮
    臨床放射線 金原出版(株) 67 (7) 683 - 692 0009-9252 2022/07
  • Yoshiaki Hosokawa, Tomohiro Onodera, Kentaro Homan, Jun Yamaguchi, Kohsuke Kudo, Hiroyuki Kameda, Hiroyuki Sugimori, Norimasa Iwasaki
    CARTILAGE 13 (3) 1947-6035 2022/07 
    Objective In the early stages of cartilage damage, diagnostic methods focusing on the mechanism of maintaining the hydrostatic pressure of cartilage are thought to be useful. O-17-labeled water, which is a stable isotope of oxygen, has the advantage of no radiation exposure or allergic reactions and can be detected by magnetic resonance imaging (MRI). This study aimed to evaluate MRI images using O-17-labeled water in a rabbit model. Design Contrast MRI with O-17-labeled water and macroscopic and histological evaluations were performed 4 and 8 weeks after anterior cruciate ligament transection surgery in rabbits. A total of 18 T2-weighted images were acquired, and O-17-labeled water was manually administered on the third scan. The O-17 concentration in each phase was calculated from the signal intensity at the articular cartilage. Macroscopic and histological grades were evaluated and compared with the O-17 concentration. Results An increase in O-17 concentration in the macroscopic and histologically injured areas was observed by MRI. Macroscopic evaluation showed that the O-17 concentration significantly increased in the damaged site group. Histological evaluations also showed that O-17 concentrations significantly increased at 36 minutes 30 seconds after initiating MRI scanning in the Osteoarthritis Research Society International (OARSI) grade 3 (0.493 in grade 0, 0.659 in grade 1, 0.4651 in grade 2, and 0.9964 in grade 3, P < 0.05). Conclusion O-17-labeled water could visualize earlier articular cartilage damage, which is difficult to detect by conventional methods.
  • Ryota Sato, Kohsuke Kudo, Niki Udo, Masaaki Matsushima, Ichiro Yabe, Akinori Yamaguchi, Khin Khin Tha, Makoto Sasaki, Masafumi Harada, Noriyuki Matsukawa, Tomoki Amemiya, Yasuo Kawata, Yoshitaka Bito, Hisaaki Ochi, Toru Shirai
    European radiology 32 (7) 4479 - 4488 2022/07 
    OBJECTIVES: Voxel-based morphometry (VBM) is widely used to quantify the progression of Alzheimer's disease (AD), but improvement is still needed for accurate early diagnosis. We evaluated the feasibility of a novel diagnosis index for early diagnosis of AD based on quantitative susceptibility mapping (QSM) and VBM. METHODS: Thirty-seven patients with AD, 24 patients with mild cognitive impairment (MCI) due to AD, and 36 cognitively normal (NC) subjects from four centers were included. A hybrid sequence was performed by using 3-T MRI with a 3D multi-echo GRE sequence to obtain both a T1-weighted image for VBM and phase images for QSM. The index was calculated from specific voxels in QSM and VBM images by using a linear support vector machine. The method of voxel extraction was optimized to maximize diagnostic accuracy, and the optimized index was compared with the conventional VBM-based index using receiver operating characteristic analysis. RESULTS: The index was optimal when voxels were extracted as increased susceptibility (AD > NC) in the parietal lobe and decreased gray matter volume (AD < NC) in the limbic system. The optimized proposed index showed excellent performance for discrimination between AD and NC (AUC = 0.94, p = 1.1 × 10-10) and good performance for MCI and NC (AUC = 0.87, p = 1.8 × 10-6), but poor performance for AD and MCI (AUC = 0.68, p = 0.018). Compared with the conventional index, AUCs were improved for all cases, especially for MCI and NC (p < 0.05). CONCLUSIONS: In this preliminary study, the proposed index based on QSM and VBM improved the diagnostic performance between MCI and NC groups compared with the VBM-based index. KEY POINTS: • We developed a novel diagnostic index for Alzheimer's disease based on quantitative susceptibility mapping (QSM) and voxel-based morphometry (VBM). • QSM and VBM images can be acquired simultaneously in a single sequence with little increasing scan time. • In this preliminary study, the proposed diagnostic index improved the discriminative performance between mild cognitive impairment and normal control groups compared with the conventional VBM-based index.
  • Ayumi Takayanagi, Fumi Kato, Ayako Nozaki, Ryuji Matsumoto, Takahiro Osawa, Ken Kuwahara, Yoshihiro Matsuno, Hiroshi Asano, Tatsuya Kato, Hidemichi Watari, Takashige Abe, Nobuo Shinohara, Kohsuke Kudo
    Radiology case reports 17 (7) 2320 - 2327 2022/07 
    A 62-year-old woman presented with a tumor in the right kidney. A right partial nephrectomy was performed, and the tumor was diagnosed as clear cell renal cell carcinoma (RCC) on histopathological examination. A right ovarian tumor was detected on follow-up computed tomography (CT) 5 years after partial nephrectomy and pathology proved RCC metastasis. RCC rarely metastasizes to the ovaries. There is limited information on the radiological features of ovarian metastasis in RCC. In this case report, we presented the CT and magnetic resonance images of ovarian metastasis of RCC. In addition, we also presented a literature review with special emphasis on the imaging features of ovarian metastasis of RCC.
  • 乳房専用超音波CTによる乳癌検出能の検討
    加藤 扶美, 佐藤 恵美, 西田 睦, 竹下 卓志, 押野 智博, 常田 慧徳, 守谷 結美, 上石 崇史, 桑山 真紀, 高橋 將人, 工藤 與亮
    日本乳癌学会総会プログラム抄録集 (一社)日本乳癌学会 30回 PO6 - 6 2022/06
  • Taisuke Harada, Kohsuke Kudo, Noriyuki Fujima, Masato Yoshikawa, Yohei Ikebe, Ryota Sato, Toru Shirai, Yoshitaka Bito, Ikuko Uwano, Mari Miyata
    Radiographics : a review publication of the Radiological Society of North America, Inc 42 (4) 210054 - 210054 2022/05/06 
    Quantitative susceptibility mapping (QSM), one of the advanced MRI techniques for evaluating magnetic susceptibility, offers precise quantitative measurements of spatial distributions of magnetic susceptibility. Magnetic susceptibility describes the magnetizability of a material to an applied magnetic field and is a substance-specific value. Recently, QSM has been widely used to estimate various levels of substances in the brain, including iron, hemosiderin, and deoxyhemoglobin (paramagnetism), as well as calcification (diamagnetism). By visualizing iron distribution in the brain, it is possible to identify anatomic structures that are not evident on conventional images and to evaluate various neurodegenerative diseases. It has been challenging to apply QSM in areas outside the brain because of motion artifacts from respiration and heartbeats, as well as the presence of fat, which has a different frequency to the proton. In this review, the authors provide a brief overview of the theoretical background and analyze methods of converting MRI phase images to QSM. Moreover, we provide an overview of the current clinical applications of QSM. Online supplemental material is available for this article. ©RSNA, 2022.
  • Taisuke Harada, Kohsuke Kudo, Hiroyuki Kameda, Ryota Sato, Toru Shirai, Yoshitaka Bito, Noriyuki Fujima, Satonori Tsuneta, Toshifumi Nogawa, Kenichiro Maeda, Hiroshi Hayashi, Makoto Sasaki
    Journal of Magnetic Resonance Imaging 1053-1807 2022/04/30
  • 日本人肥満2型糖尿病における腹腔鏡下スリーブ状胃切除術が脂肪肝に及ぼす効果 前向きコホート研究
    大江 悠希, 高瀬 崇宏, 曹 圭龍, 小川 浩司, 海老原 裕磨, 吉川 仁人, 西田 睦, 宮 愛香, 野本 博司, 亀田 啓, 荘 拓也, 須田 剛生, 中村 昭伸, 倉島 庸, 阿保 大介, 工藤 與亮, 坂本 直哉, 平野 聡, 渥美 達也, 三好 秀明
    糖尿病 (一社)日本糖尿病学会 65 (Suppl.1) S - 139 0021-437X 2022/04
  • 頸動脈プラークQSMの画質(artifact)改善のための撮影技術
    川崎 智博, 石坂 欣也, 池辺 洋平, 原田 邦明, 白勢 竜二, 佐藤 良太, 工藤 與亮
    北海道放射線技術雑誌 (公社)日本放射線技術学会-北海道支部 (92) 36 - 37 0912-0327 2022/04
  • Takuya Aoike, Noriyuki Fujima, Masami Yoneyama, Taro Fujiwara, Sayaka Takamori, Suzuko Aoike, Kinya Ishizaka, Kohsuke Kudo
    Magnetic resonance imaging 87 32 - 37 2022/04 
    PURPOSE: To assess the cervical magnetic resonance neurography (MRN) imaging quality obtained with compressed sensing and sensitivity-encoding (compressed SENSE; CS-SENSE) technique in comparison to that obtained with the conventional parallel imaging (i.e., SENSE) technique. MATERIALS AND METHODS: Five healthy volunteers underwent a three-dimensional (3D) turbo spin-echo (TSE)-based cervical MRN examination using a 3.0 Tesla MR-unit. All MRN acquisitions were performed with CS-SENSE and conventional SENSE. We used four acceleration factors (4, 8, 16 and 32) in CS-SENSE. The image quality in MRN was evaluated by assessing the degree of cervical nerve depiction using the contrast ratio (CR) and contrast-noise ratio (CNR) between the cervical nerve and the background signal intensity and a visual scoring system (1: poor, 2: moderate, 3: good). In all of the CR, CNR and visual score, we calculated the ratio of the CS-SENSE-based MRN to that from SENSE-based MRN plus the 95% confidence intervals (CIs) of these ratios. RESULTS: In the multiple comparison of MRN images with the control of conventional SENSE-based MRN, both the quantitative CR values and the visual score for the CS-SENSE factors of 16 and 32 were significantly lower, whereas the CS-SENSE factors of 4 and 8 showed a non-significant difference. In addition, the quantitative CNR values obtained with the CS-SENSE factors of 4 and 8 were significantly higher than that obtained with the conventional SENSE-based MRN while the CS-SENSE factor of 32 was significantly lower, in contrast, the CS-SENSE factors of 16 showed a non-significant difference. For CS-SENSE factors of 4 and 8, all ratios of the CS-SENSE-based MRN values for CR, CNR and visual scores to those from SENSE-based MRN were above 0.95. CONCLUSION: CS-SENSE-based MRN can accomplish fast scanning with sufficient image quality when using a high acceleration factor.
  • Hiroyuki Sugimori, Hiroyuki Kameda, Taisuke Harada, Kinya Ishizaka, Masayoshi Kajiyama, Tasuku Kimura, Niki Udo, Masaaki Matsushima, Azusa Nagai, Masahiro Wakita, Ichiro Kusumi, Ichiro Yabe, Kohsuke Kudo
    Magnetic resonance imaging 87 77 - 85 2022/04 
    The aim of this study was to evaluate the feasibility of kinetic analysis of cerebrospinal fluid (CSF) using 17O-labeled water tracer. Four subjects (two idiopathic normal pressure hydrocephalus (iNPH) and two possible AD dementia patients) were prospectively included. Injectable formulation of 17O-labeled water containing 10 mol% of H217O (PSO17), was intrathecally administered to the subjects with the lateral decubitus position between the 3rd and 4th lumbar vertebrae. MRI acquisitions were performed in four-time points, before PSO17 administration, 1, 8, and 24 h after PSO17 administration. The 3-dimensional fast spin echo sequence was used. After image registration for all four-time points data, polygonal regions of interest (ROIs) were set in the 14 regions to obtain the signal intensity of CSF. Each signal intensity within the ROI was converted to 17O concentration [%]. The peak concentration at one hour after administration, the slope of concentration changes after PSO17 administration [%/s], and the root mean square error (RMSE) for evaluating the performance of a fitting were calculated. There was no significant difference in peak concentration between the iNPH and AD group. The slope in the AD group (-2.25 ± 1.62 × 10-3 [%/h]) was significantly smaller than in the iNPH group (-1.21 ± 2.31 × 10-3 [%/h]), which suggests the speed of CSF clearance in the iNPH group was slower than AD group. The RMSE indicating the fit to the concentration change in the AD group (4.86 ± 4.74 × 10-3) was also significantly smaller than in the iNPH group (8.64 ± 7.56 × 10-3). The kinetic evaluation of CSF using 17O-labeled water was feasible, and this preliminary study suggests that the differentiation of iNPH and possible AD dementia can be achieved using this method.
  • Kanta Tanaka, Kaori Miwa, Masahito Takagi, Makoto Sasaki, Yusuke Yakushiji, Kohsuke Kudo, Masayuki Shiozawa, Jun Tanaka, Masashi Nishihara, Yoshitaka Yamaguchi, Kyohei Fujita, Yuko Honda, Hiroyuki Kawano, Toshihiro Ide, Sohei Yoshimura, Masatoshi Koga, Teruyuki Hirano, Kazunori Toyoda
    Journal of the American Heart Association 11 (6) e024749  2022/03/15 
    Background The aim of this study was to determine the associations of cerebral small vessel disease (SVD) burden with renal dysfunction and albuminuria in patients taking oral antithrombotic agents. Methods and Results Patients who newly started or continued taking oral antiplatelets or anticoagulants were enrolled in a prospective, multicenter, observational study. Obligatorily acquired multimodal magnetic resonance imaging at registration with prespecified imaging conditions was assessed for cerebral microbleeds, white matter hyperintensities, enlarged basal ganglia perivascular spaces, or lacunes, and an ordinal SVD score was calculated (range, 0-4). Multivariable adjusting covariates were age, sex, hypertension, diabetes, dyslipidemia, current smoking, drinking, and estimated glomerular filtration rate (eGFR). Of 5324 patients (1762 women; median age, 73 years), 4797 (90.1%) patients were taking oral antithrombotic agents for secondary stroke prevention. Cerebral microbleeds were present in 32.7%, confluent white matter hyperintensities in 51.8%, extensive basal ganglia perivascular spaces in 38.9%, and lacunes in 59.4%. Median SVD score was 2. Compared with eGFR category G1 (eGFR ≥90 mL/min per 1.73 m2), adjusted odds ratios for SVD score increment were 1.63 (95% CI, 1.11-2.39) at category G4 (eGFR 15-<30 mL/min per 1.73 m2) and 2.05 (95% CI, 1.33-3.16) at G5 (eGFR <15 mL/min per 1.73 m2). Corresponding odds ratios relative to urinary albumin-to-creatinine ratio (ACR) category A1 (ACR <30 mg/g) were 1.29 (95% CI, 1.12-1.49) for category A2 (ACR 30-<300 mg/g) and 1.37 (95% CI, 1.05-1.77) for A3 (ACR ≥300 mg/g). When combined eGFR and ACR categories were assessed, risks for SVD score increment generally increased as eGFR decreased and ACR increased. Conclusions Both reduced eGFR and albuminuria were independently associated with increased cerebral SVD burden in patients requiring oral antithrombotic medication mainly for secondary stroke prevention. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT01581502; URL: https://www.umin.ac.jp/ctr; Unique identifier: UMIN000023669.
  • Akinori Yamaguchi, Kohsuke Kudo, Ryota Sato, Yasuo Kawata, Niki Udo, Masaaki Matsushima, Ichiro Yabe, Makoto Sasaki, Masafumi Harada, Noriyuki Matsukawa, Toru Shirai, Hisaaki Ochi, Yoshitaka Bito
    Magnetic resonance in medical sciences : MRMS : an official journal of Japan Society of Magnetic Resonance in Medicine 2022/03/10 
    PURPOSE: Studies on quantitative susceptibility mapping (QSM) have reported an increase in magnetic susceptibilities in patients with Alzheimer's disease (AD). Despite the pathological importance of the brain surface areas, they are sometimes excluded in QSM analysis. This study aimed to reveal the efficacy of QSM analysis with brain surface correction (BSC) and/or vein removal (VR) procedures. METHODS: Thirty-seven AD patients and 37 age- and sex-matched, cognitively normal (CN) subjects were included. A 3D-gradient echo sequence at 3T MRI was used to obtain QSM. QSM images were created with regularization enabled sophisticated harmonic artifact reduction for phase data (RESHARP) and constrained RESHARP with BSC and/or VR. We conducted ROI analysis between AD patients and CN subjects who did or did not undergo BSC and/or VR using a t-test, to compare the susceptibility values after gray matter weighting. RESULTS: The susceptibility values in RESHARP without BSC were significantly larger in AD patients than in CN subjects in one region (precentral gyrus, 8.1 ± 2.9 vs. 6.5 ± 2.1 ppb) without VR and one region with VR (precentral gyrus, 7.5 ± 2.8 vs. 5.9 ± 2.0 ppb). Three regions in RESHARP with BSC had significantly larger susceptibilities without VR (precentral gyrus, 7.1 ± 2.0 vs. 5.9 ± 2.0 ppb; superior medial frontal gyrus, 5.7 ± 2.6 vs. 4.2 ± 3.1 ppb; putamen, 47,8 ± 16.5 vs. 40.0 ± 15.9 ppb). In contrast, six regions showed significantly larger susceptibilities with VR in AD patients than in CN subjects (precentral gyrus, 6.4 ± 1.9 vs. 4.9 ± 2.7 ppb; superior medial frontal gyrus, 5.3 ± 2.7 vs. 3.7 ± 3.3 ppb; orbitofrontal cortex, -2.1 ± 2.7 vs. -3.6 ± 3.2 ppb; parahippocampal gyrus, 0.1 ± 3.6 vs. -1.7 ± 3.7 ppb; putamen, 45.0 ± 14.9 vs. 37.6 ± 14.6 ppb; inferior temporal gyrus, -3.4 ± 1.5 vs. -4.4 ± 1.5 ppb). CONCLUSION: RESHARP with BSC and VR showed more regions of increased susceptibility in AD patients than in CN subjects. This study highlights the efficacy of this method in facilitating the diagnosis of AD.
  • 肺癌の再発・転移が疑われた後縦隔FDG陽性病変の診断に骨髄シンチグラフィが有用であった一例
    眞島 隆成, 竹中 淳規, 渡邊 史郎, 内山 裕子, 木村 理奈, 榊原 純, 平田 健司, 工藤 與亮
    北海道放射線医学雑誌 (NPO)メディカルイメージラボ 2 29 - 33 2022/03 
    後縦隔傍脊椎部に発生した髄外造血の一例を経験したので報告する。症例は70歳代男性。原発性肺癌の術後経過観察中に胸部CTにて第5/6胸椎腹側に軟部腫瘤の出現を指摘され、その後も腫瘤は増大傾向を示した。18F-FDG PET/CTでの集積亢進も認め、術後再発や転移性腫瘍、その他悪性リンパ腫や神経原性腫瘍等が鑑別となったが、画像経過からは腫瘤は経時的な増大とともに形態の変化も認めていた。この経過からは髄外造血が疑われたが、病変の局在としてはやや非典型であった。診断目的に気管支鏡下または外科的生検も検討されたが、出血リスクの高い髄外造血の除外のためインジウム(111In)シンチグラフィを施行したところ、腫瘤に一致したインジウムの集積を認め、髄外造血と診断した。その後も経過観察し、腫瘤は自然消退した。髄外造血は肝臓、脾臓、リンパ節などにみられるが、胸腔内、なかでも後縦隔の傍脊椎領域にも発生する。後縦隔傍脊椎部に腫瘤を認めた場合には髄外造血を念頭に置く必要があり、骨髄シンチグラフィにより侵襲的検査を回避可能な場合がある。(著者抄録)
  • 演繹法と帰納法の視点から見た医療AI
    平田 健司, 杉森 博行, 唐 明輝, 中谷 純, 小笠原 克彦, 豊永 拓哉, 工藤 與亮
    北海道放射線医学雑誌 (NPO)メディカルイメージラボ 2 1 - 6 2022/03 
    医療AIが目覚ましい発達を続けている。AIに関する明確な定義はないため、今回、医療従事者等に対してAIに関する意識調査を行った結果、AIであるかどうかの境界線は、機械学習の有無にありそうだということがわかった。機械学習は帰納法に基づく考え方であり、あらかじめ多数のデータを学習させておくことで、明示的にルールを与えずとも未知の事例を正しく判断させる手法である。画像分類においては明示的ルールを与えることが困難であるため、機械学習が威力を発揮する。第3次AIブームの現在、AIといえば機械学習に基づくAIのことを指すことが多い。これに対して、第1次、第2次AIブームでは推論、探索、エキスパートシステムといった演繹法に基づくAIが盛んに研究されたが成功せず、冬の時代を経験した。我々は、帰納法のみのAIではいずれ限界に到達する可能性があり、演繹法の手法をいかに組み合わせていくかが今後の課題になっていくと考えている。(著者抄録)
  • 演繹法と帰納法の視点から見た医療AI
    平田 健司, 杉森 博行, 唐 明輝, 中谷 純, 小笠原 克彦, 豊永 拓哉, 工藤 與亮
    北海道放射線医学雑誌 (NPO)メディカルイメージラボ 2 1 - 6 2022/03 
    医療AIが目覚ましい発達を続けている。AIに関する明確な定義はないため、今回、医療従事者等に対してAIに関する意識調査を行った結果、AIであるかどうかの境界線は、機械学習の有無にありそうだということがわかった。機械学習は帰納法に基づく考え方であり、あらかじめ多数のデータを学習させておくことで、明示的にルールを与えずとも未知の事例を正しく判断させる手法である。画像分類においては明示的ルールを与えることが困難であるため、機械学習が威力を発揮する。第3次AIブームの現在、AIといえば機械学習に基づくAIのことを指すことが多い。これに対して、第1次、第2次AIブームでは推論、探索、エキスパートシステムといった演繹法に基づくAIが盛んに研究されたが成功せず、冬の時代を経験した。我々は、帰納法のみのAIではいずれ限界に到達する可能性があり、演繹法の手法をいかに組み合わせていくかが今後の課題になっていくと考えている。(著者抄録)
  • Yuto Uchida, Hirohito Kan, Hiroyasu Inoue, Masahiro Oomura, Haruto Shibata, Yuya Kano, Tomoyuki Kuno, Toshihiko Usami, Koji Takada, Kentaro Yamada, Kohsuke Kudo, Noriyuki Matsukawa
    Frontiers in Neurology 13 2022/02/11 
    BackgroundThe oxygen extraction fraction (OEF) has been applied to identify ischemic penumbral tissue, but is difficult to use in an urgent care setting. This study aimed to investigate whether an OEF map generated via magnetic resonance quantitative susceptibility mapping (QSM) could help identify the ischemic penumbra in patients with acute ischemic stroke. Materials and MethodsThis prospective imaging study included 21 patients with large anterior circulation vessel occlusion who were admitted &lt;24 h after stroke onset and 21 age-matched healthy controls. We identified the ischemic penumbra as the region with a Tmax of &gt;6 s during dynamic susceptibility contrast-magnetic resonance imaging (DSC-MRI) and calculated the perfusion-core mismatch ratio between the ischemic penumbra and infarct core volumes. The OEF values were measured based on magnetic susceptibility differences between the venous structures and brain tissues using rapid QSM acquisition. Volumes with increased OEF values were compared to the ischemic penumbra volumes using an anatomical template. ResultsEleven patients had a perfusion-core mismatch ratio of ≥1.8, and reperfusion therapy was recommended. In these patients, the volumes with increased OEF values of &gt;51.5%, which was defined using the anterior circulation territory OEF values from the 21 healthy controls, were positively correlated with the ischemic penumbra volumes (r = 0.636, 95% CI: 0.059 to 0.895, P = 0.035) and inversely correlated with the 30-day change in the National Institutes of Health Stroke Scale scores (r = −0.624, 95% CI: −0.891 to −0.039, P = 0.041). ConclusionTissue volumes with increased OEF values could predict ischemic penumbra volumes based on DSC-MRI, highlighting the potential of the QSM-derived OEF map as a penumbra biomarker to guide treatment selection in patients with acute ischemic stroke.
  • Kenji Hirata, Hiroyuki Sugimori, Noriyuki Fujima, Takuya Toyonaga, Kohsuke Kudo
    Annals of nuclear medicine 36 (2) 123 - 132 2022/02 
    As in all other medical fields, artificial intelligence (AI) is increasingly being used in nuclear medicine for oncology. There are many articles that discuss AI from the viewpoint of nuclear medicine, but few focus on nuclear medicine from the viewpoint of AI. Nuclear medicine images are characterized by their low spatial resolution and high quantitativeness. It is noted that AI has been used since before the emergence of deep learning. AI can be divided into three categories by its purpose: (1) assisted interpretation, i.e., computer-aided detection (CADe) or computer-aided diagnosis (CADx). (2) Additional insight, i.e., AI provides information beyond the radiologist's eye, such as predicting genes and prognosis from images. It is also related to the field called radiomics/radiogenomics. (3) Augmented image, i.e., image generation tasks. To apply AI to practical use, harmonization between facilities and the possibility of black box explanations need to be resolved.
  • Yukitomo Ishi, Taisuke Harada, Hiroyuki Kameda, Hiromi Okada, Isao Yokota, Michinari Okamoto, Ryosuke Sawaya, Hiroaki Motegi, Shigeru Yamaguchi, Shunsuke Terasaka, Kohsuke Kudo, Miki Fujimura
    Neuroradiology 64 (2) 393 - 396 2022/02 
    The study aimed to investigate the clinical implications and natural history of primary intraparenchymal lesions in patients with neurofibromatosis type 2. Radiological findings of 15 neurofibromatosis type 2 cases were retrospectively collected. Twenty-seven primary intraparenchymal lesions were observed in 7 out of 15 patients (47%). Cortical/subcortical T2 hyperintense lesions and enlarged Virchow-Robin spaces were the most common findings in five and four patients, respectively. During the follow-up period (median 84 months), one new primary intraparenchymal lesion was identified and increased lesions were observed in two cases on contrast-enhanced MRI. Surgical resection was performed in one case pathologically diagnosed with atypical meningioma. Twenty-five other lesions without contrast enhancement presented no apparent growth during follow-up. Although most primary intraparenchymal lesions are benign, a subset of cases would present newly developed or increased lesions on contrast-enhanced MRI. Careful monitoring is necessary for such cases, and pathological confirmation should be considered.
  • Chie Tsuruta, Kenji Hirata, Kohsuke Kudo, Naoya Masumori, Masamitsu Hatakenaka
    European radiology experimental 6 (1) 1 - 1 2022/01/12 
    BACKGROUND: We investigated the correlation between texture features extracted from apparent diffusion coefficient (ADC) maps or diffusion-weighted images (DWIs), and grade group (GG) in the prostate peripheral zone (PZ) and transition zone (TZ), and assessed reliability in repeated examinations. METHODS: Patients underwent 3-T pelvic magnetic resonance imaging (MRI) before radical prostatectomy with repeated DWI using b-values of 0, 100, 1,000, and 1,500 s/mm2. Region of interest (ROI) for cancer was assigned to the first and second DWI acquisition separately. Texture features of ROIs were extracted from comma-separated values (CSV) data of ADC maps generated from several sets of two b-value combinations and DWIs, and correlation with GG, discrimination ability between GG of 1-2 versus 3-5, and data repeatability were evaluated in PZ and TZ. RESULTS: Forty-four patients with 49 prostate cancers met the eligibility criteria. In PZ, ADC 10% and 25% based on ADC map of two b-value combinations of 100 and 1,500 s/mm2 and 10% based on ADC map with b-value of 0 and 1,500 s/mm2 showed significant correlation with GG, acceptable discrimination ability, and good repeatability. In TZ, higher-order texture feature of busyness extracted from ADC map of 100 and 1,500 s/mm2, and high gray-level run emphasis, short-run high gray-level emphasis, and high gray-level zone emphasis from DWI with b-value of 100 s/mm2 demonstrated significant correlation, excellent discrimination ability, but moderate repeatability. CONCLUSIONS: Some DWI-related features showed significant correlation with GG, acceptable to excellent discrimination ability, and moderate to good data repeatability in prostate cancer, and differed between PZ and TZ.
  • Tsubasa Kunieda, Ren Togo, Noriko Nishioka, Yukie Shimizu, Shiro Watanabe, Kenji Hirata, Keisuke Maeda, Takahiro Ogawa 0001, Kohsuke Kudo, Miki Haseyama
    GCCE 137 - 138 2022
  • Sho Sosogi, Daisuke Abo, Ryo Morita, Takeshi Soyama, Bunya Takahashi, Yuki Yoshino, Koji Yamasaki, Noriyuki Miyamoto, Kohsuke Kudo
    Interventional Radiology 2022
  • 池辺 洋平, 藤間 憲幸, 工藤 與亮
    臨床画像 (株)メジカルビュー社 37 (12) 1390 - 1402 0911-1069 2021/12 
    <文献概要>椎骨動脈解離は種々のシーケンスを用いて解離を同定する必要があり,3D-TSE(turbo spin-echo)法T1強調像やMR cisternographyが有用な場合がある。静脈血栓症は正常例や種々の疾患との鑑別が問題となり,診断確定には造影MRV(MR venography)が有用である。メトロニダゾール脳症は小脳歯状核の異常信号が特徴で,詳細な病歴の確認が重要である。低髄液圧症候群/脳脊髄液漏出症は髄液減少に伴う特徴的な所見を積極的に検索することで診断できる。
  • Noriyuki Fujima, V. Carlota Andreu-Arasa, Sara K. Meibom, Gustavo A. Mercier, Minh Tam Truong, Kenji Hirata, Koichi Yasuda, Satoshi Kano, Akihiro Homma, Kohsuke Kudo, Osamu Sakai
    BMC Cancer 21 (1) 900 - 900 2021/12 [Refereed][Not invited]
     
    Abstract Background This study aimed to assess the utility of deep learning analysis using pretreatment FDG-PET images to predict local treatment outcome in oropharyngeal squamous cell carcinoma (OPSCC) patients. Methods One hundred fifty-four OPSCC patients who received pretreatment FDG-PET were included and divided into training (n = 102) and test (n = 52) sets. The diagnosis of local failure and local progression-free survival (PFS) rates were obtained from patient medical records. In deep learning analyses, axial and coronal images were assessed by three different architectures (AlexNet, GoogLeNET, and ResNet). In the training set, FDG-PET images were analyzed after the data augmentation process for the diagnostic model creation. A multivariate clinical model was also created using a binomial logistic regression model from a patient’s clinical characteristics. The test data set was subsequently analyzed for confirmation of diagnostic accuracy. Assessment of local PFS rates was also performed. Results Training sessions were successfully performed with an accuracy of 74–89%. ROC curve analyses revealed an AUC of 0.61–0.85 by the deep learning model in the test set, whereas it was 0.62 by T-stage, 0.59 by clinical stage, and 0.74 by a multivariate clinical model. The highest AUC (0.85) was obtained with deep learning analysis of ResNet architecture. Cox proportional hazards regression analysis revealed deep learning-based classification by a multivariate clinical model (P < .05), and ResNet (P < .001) was a significant predictor of the treatment outcome. In the Kaplan-Meier analysis, the deep learning-based classification divided the patient’s local PFS rate better than the T-stage, clinical stage, and a multivariate clinical model. Conclusions Deep learning-based diagnostic model with FDG-PET images indicated its possibility to predict local treatment outcomes in OPSCCs.
  • Zongyao Li, Kazuhiro Kitajima, Kenji Hirata, Ren Togo, Junki Takenaka, Yasuo Miyoshi, Kohsuke Kudo, Takahiro Ogawa, Miki Haseyama
    EJNMMI Research 11 (1) 2191-219X 2021/12 [Refereed][Not invited]
     
    Abstract Background To improve the diagnostic accuracy of axillary lymph node (LN) metastasis in breast cancer patients using 2-[18F]FDG-PET/CT, we constructed an artificial intelligence (AI)-assisted diagnosis system that uses deep-learning technologies. Materials and methods Two clinicians and the new AI system retrospectively analyzed and diagnosed 414 axillae of 407 patients with biopsy-proven breast cancer who had undergone 2-[18F]FDG-PET/CT before a mastectomy or breast-conserving surgery with a sentinel lymph node (LN) biopsy and/or axillary LN dissection. We designed and trained a deep 3D convolutional neural network (CNN) as the AI model. The diagnoses from the clinicians were blended with the diagnoses from the AI model to improve the diagnostic accuracy. Results Although the AI model did not outperform the clinicians, the diagnostic accuracies of the clinicians were considerably improved by collaborating with the AI model: the two clinicians' sensitivities of 59.8% and 57.4% increased to 68.6% and 64.2%, respectively, whereas the clinicians' specificities of 99.0% and 99.5% remained unchanged. Conclusions It is expected that AI using deep-learning technologies will be useful in diagnosing axillary LN metastasis using 2-[18F]FDG-PET/CT. Even if the diagnostic performance of AI is not better than that of clinicians, taking AI diagnoses into consideration may positively impact the overall diagnostic accuracy.
  • Shunichi Yokota, Keita Sakamoto, Yukie Shimizu, Tsuyoshi Asano, Daisuke Takahashi, Kohsuke Kudo, Norimasa Iwasaki, Tomohiro Shimizu
    Arthritis Research & Therapy 23 (1) 2021/12 [Refereed][Not invited]
     
    Abstract Background This study aimed to investigate the ability of whole-body bone scintigraphy (WB-BS) in the detection of multifocal osteonecrosis (ON) compared to whole-body magnetic resonance imaging (WB-MRI) and to clarify the characteristics of patients with multifocal ON among those with ON of the femoral head (ONFH) using WB-MRI. Methods Forty-six patients who had symptomatic ONFH and underwent surgery in our hospital from April 2019 to October 2020 were included in the study. Data on patient demographics, including age, sex, body mass index (BMI), history of corticosteroid intake, alcohol abuse, smoking, and symptomatic joints, were collected from their medical records. All patients underwent WB-MRI and WB-BS before surgery. Results The agreement in the detection of ON by WB-MRI vs the uptake lesions by WB-BS in the hip joints was moderate (κ = 0.584), while that in other joints was low (κ < 0.40). Among the 152 joints with ON detected by WB-MRI, 92 joints (60.5%) were symptomatic, and 60 joints (39.5%) were asymptomatic. Twelve out of the 46 (26.0%) patients had multifocal (three or more distinct anatomical sites) ON. Nonetheless, while WB-BS detected symptomatic ON detected by WB-MRI as uptake lesions in 82.6% (76/92) of the joints, asymptomatic ON detected by WB-MRI was detected as uptake lesions in 21.7% (13/60) of the joints. All patients with multifocal ON had a history of steroid therapy, which was significantly higher than that in patients with oligofocal ON (P = 0.035). The patients with a hematologic disease had multifocal ON at a higher rate (P = 0.015). Conclusions It might be difficult for WB-BS to detect the asymptomatic ON detected by WB-MRI compared to symptomatic ON. Considering the cost, examination time, and radiation exposure, WB-MRI might be useful for evaluating multifocal ON. Larger longitudinal studies evaluating the benefits of WB-MRI for detecting the risk factors for multifocal ON are required.
  • Yuki Oe, Hiraku Kameda, Hiroshi Nomoto, Keita Sakamoto, Takeshi Soyama, Kyu Yong Cho, Akinobu Nakamura, Koji Iwasaki, Daisuke Abo, Kohsuke Kudo, Hideaki Miyoshi, Tatsuya Atsumi
    Medicine 100 (46) e27895  2021/11/19 
    RATIONALE: Tumor-induced osteomalacia (TIO) is curable by tumor resection, but detection of the tumor can be challenging. Overproduction of fibroblast growth factor 23 (FGF23) by the tumor causes hypophosphatemia and consequently induces inappropriate bone turnover. Conventionally oral phosphate supplementation was the only treatment for TIO, but had risks of hypercalciuria and nephrocalcinosis. Burosumab, a human monoclonal anti-FGF23 antibody, was recently post-marketed in Japan against for FGF23-related hypophosphatemia. Herein, we present a case of TIO with undetectable tumor that was successfully treated with burosumab. PATIENT CONCERNS: A 47-year-old woman was forced to use a wheelchair because of pain in both feet. DIAGNOSIS: Laboratory findings showed hypophosphatemia, elevated bone markers, and high serum FGF23 without renal tubular defects. Imaging studies revealed bone atrophy in the feet, decreased bone density, and multiple pseudofractures in the talar, sacral, and L5 vertebral regions. After excluding drug-induced and hereditary osteomalacia, we diagnosed her as TIO. INTERVENTIONS: Comprehensive imaging studies and stepwise venous sampling failed to localize the tumor, and we started to administer subcutaneous burosumab. OUTCOMES: After administration of burosumab, her serum phosphate was normalized without phosphate supplementation within 2 months. Improvement of pseudofractures, relief of pain evaluated by a visual analog scale, and normalization of bone biomarkers were observed. The patient was able to stand by herself after 6 months administration of burosumab. LESSONS: This is the first report in clinical practice to demonstrate favorable effects of burosumab, including not only normalization of serum phosphate but also improvements of pseudofractures and subjective pain, in a patient with TIO and undetectable tumor.
  • 阿保 大介, 曽山 武士, 森田 亮, 高橋 文也, 木野田 直也, 安井 太一, 工藤 與亮
    日本外科感染症学会雑誌 (一社)日本外科感染症学会 18 (1) 155 - 155 1349-5755 2021/11
  • T. Yoshimura, K. Nishioka, T. Hashimoto, S. Kogame, K. Seki, H. Sugimori, H. Yamashina, F. Kato, H. Aoyama, K. Kudo, S. Shimizu
    International Journal of Radiation Oncology*Biology*Physics 111 (3) e121 - e122 0360-3016 2021/11
  • SiPM-PET/CT装置を用いた冠動脈18F-FDG集積の再現性評価
    渡邊 史郎, 納谷 昌直, 孫田 恵一, 真鍋 治, 新山 大樹, 平田 健司, 内山 裕子, 竹中 淳規, 工藤 與亮
    核医学 (一社)日本核医学会 58 (Suppl.) S210 - S210 0022-7854 2021/10
  • FDG-PET/CTのレポート上のSUVmaxを利用して解剖学用語を機械学習させる検討
    平田 健司, 渡邊 史郎, 内山 裕子, 竹中 淳規, 木村 理奈, 眞島 隆成, 孫田 恵一, 工藤 與亮
    核医学 (一社)日本核医学会 58 (Suppl.) S225 - S225 0022-7854 2021/10
  • 頸動脈プラークQSMの画質(artifact)改善のための撮影技術
    川崎 智博, 石坂 欣也, 原田 邦明, 池辺 洋平, 工藤 與亮, 白勢 竜二, 佐藤 良太
    北海道放射線技術雑誌 (公社)日本放射線技術学会-北海道支部 (91) 56 - 56 0912-0327 2021/10
  • 宮崎 あすか, 亀田 啓, 大江 悠希, 泉原 里美, 重沢 郁美, 野本 博司, 曹 圭龍, 中村 昭伸, 坂本 圭太, 森田 亮, 曽山 武士, 阿保 大介, 工藤 與亮, 三好 秀明, 渥美 達也
    日本内分泌学会雑誌 (一社)日本内分泌学会 97 (2) 521 - 521 0029-0661 2021/10
  • Yuta Kobayashi, Takuma Sato, Toshiyuki Nagai, Kenji Hirata, Satonori Tsuneta, Yoshiya Kato, Hirokazu Komoriyama, Kiwamu Kamiya, Takao Konishi, Kazunori Omote, Hiroshi Ohira, Kohsuke Kudo, Satoshi Konno, Toshihisa Anzai
    ESC Heart Failure 8 (6) 5282 - 5292 2055-5822 2021/09/12 [Refereed][Not invited]
     
    AIMS: Although soluble interleukin 2 receptor (sIL-2R) is a potentially useful biomarker in the diagnosis and evaluation of disease severity in patients with sarcoidosis, its prognostic implication in patients with cardiac sarcoidosis (CS) is unclear. We sought to investigate whether sIL-2R was associated with clinical outcomes and to clarify the relationship between sIL-2R levels and disease activity in patients with CS. METHODS AND RESULTS: We examined 83 consecutive patients with CS in our hospital who had available serum sIL-2R data between May 2003 and February 2020. The primary outcome was a composite of advanced atrioventricular block, ventricular tachycardia or ventricular fibrillation, heart failure hospitalization, and all-cause death. Inflammatory activity in the myocardium and lymph nodes was assessed by 18 F-fluorideoxyglucose positron emission tomography/computed tomography. During a median follow-up period of 2.96 (IQR 2.24-4.27) years, the primary outcome occurred in 24 patients (29%). Higher serum sIL-2R levels (>538 U/mL, the median) were significantly related to increased incidence of primary outcome (P = 0.037). Multivariable Cox regression analysis showed that a higher sIL-2R was independently associated with an increased subsequent risk of adverse events (HR 3.71, 95% CI 1.63-8.44, P = 0.002), even after adjustment for significant covariates. sIL-2R levels were significantly correlated to inflammatory activity in lymph nodes (r = 0.346, P = 0.003) but not the myocardium (r = 0.131, P = 0.27). CONCLUSIONS: Increased sIL-2R is associated with worse long-term clinical outcomes accompanied by increased systemic inflammatory activity in CS patients.
  • Masato Yoshikawa, Kohsuke Kudo, Taisuke Harada, Kazutaka Harashima, Jun Suzuki, Koji Ogawa, Taro Fujiwara, Mutsumi Nishida, Ryota Sato, Toru Shirai, Yoshitaka Bito
    Magnetic resonance in medical sciences : MRMS : an official journal of Japan Society of Magnetic Resonance in Medicine 2021/09/04 
    PURPOSE: The staging of liver fibrosis is clinically important, and a less invasive method is preferred. Quantitative susceptibility mapping (QSM) has shown a great potential in estimating liver fibrosis in addition to R2* relaxometry. However, few studies have compared QSM analysis and liver fibrosis. We aimed to evaluate the feasibility of estimating liver fibrosis by using QSM and R2*-based histogram analyses by comparing it with ultrasound-based transient elastography and the stage of histologic fibrosis. METHODS: Fourteen patients with liver disease were enrolled. Data sets of multi-echo gradient echo sequence with breath-holding were acquired on a 3-Tesla scanner. QSM and R2* were reconstructed by water-fat separation method, and ROIs were analyzed for these images. Quantitative parameters with histogram features (mean, variance, skewness, kurtosis, and 1st, 10th, 50th, 90th, and 99th percentiles) were extracted. These data were compared with the elasticity measured by ultrasound transient elastography and histological stage of liver fibrosis (F0 to F4, based on the new Inuyama classification) determined by biopsy or hepatectomy. The correlation of histogram parameters with intrahepatic elasticity and histologically confirmed fibrosis stage was examined. Texture parameters were compared between subgroups divided according to fibrosis stage. Receiver operating characteristic (ROC) analysis was also performed. P < 0.05 indicated statistical significance. RESULTS: The six histogram parameters of both QSM and R2*were significantly correlated with intrahepatic elasticity. In particular, three parameters (variance, percentiles [90th and 99th]) of QSM showed high correlation (r = 0.818-0.844), whereas R2* parameters showed a moderate correlation with elasticity. Four parameters of QSM were significantly correlated with fibrosis stage (ρ = 0.637-0.723) and differentiated F2-4 from F0-1 fibrosis and F3-4 from F0-2 fibrosis with areas under the ROC curve of > 0.8, but those of R2* did not. CONCLUSION: QSM may serve as a promising surrogate indicator in detecting liver fibrosis.
  • 平田 健司, 藤間 憲幸, 杉森 博行, 工藤 與亮
    INNERVISION (株)インナービジョン 36 (10) 17 - 20 0913-8919 2021/09
  • 【Nuclear Medicine Today 2021 キーワードから展望する核医学の技術開発と臨床応用】人工知能(AI)の研究開発の現状と将来展望 1)腫瘍核医学におけるAI利用の動向
    平田 健司, 藤間 憲幸, 杉森 博行, 工藤 與亮
    INNERVISION (株)インナービジョン 36 (10) 17 - 20 0913-8919 2021/09
  • Yoshitaka Bito, Kuniaki Harada, Hisaaki Ochi, Kohsuke Kudo
    Magnetic Resonance in Medicine 86 (3) 1369 - 1382 0740-3194 2021/09 [Refereed][Not invited]
  • Masatoshi Koga, Manabu Inoue, Kanta Tanaka, Tetsu Satow, Tetsuya Fukuda, Masafumi Ihara, Ryo Itabashi, Kohsuke Kudo, Hiroshi Yamagami, Kazunori Toyoda
    Rinsho shinkeigaku = Clinical neurology 61 (8) 517 - 521 2021/08/30 
    Imaging diagnosis is essential to perform appropriate reperfusion therapy for acute ischemic stroke. To equally perform reperfusion therapy all over in Japan, it is important to properly facilitate acute imaging evaluation for stroke suspected patients by medical staff not only in stroke-specialized hospitals but also in non-stroke-specialized hospitals. It is unique that CT and MRI are available in most of Japanese hospitals. Even in non-stroke-specialized hospitals, inpatients may suffer from in-hospital stroke. We review statements and recommendation items for a diagnostic imaging to appropriately perform reperfusion therapy based on major clinical trials, stroke guidelines and the current status of acute stroke imaging in Japan.
  • Yuko Uchiyama, Kenji Hirata, Shiro Watanabe, Shozo Okamoto, Tohru Shiga, Kazufumi Okada, Yoichi M. Ito, Kohsuke Kudo
    Annals of Nuclear Medicine 0914-7187 2021/08/11 [Refereed][Not invited]
  • 肝胆膵術後膵液瘻のドレナージ治療の基本と工夫
    阿保 大介, 曽山 武士, 森田 亮, 高橋 文也, 木野田 直也, 工藤 與亮
    日本医学放射線学会秋季臨床大会抄録集 (公社)日本医学放射線学会 57回 S370 - S370 0048-0428 2021/08
  • Ryo Morita, Daisuke Abo, Naoya Kinota, Takeshi Soyama, Bunya Takahashi, Yuki Yoshino, Satonori Tsuneta, Kohsuke Kudo
    Radiology Case Reports 16 (8) 2007 - 2011 1930-0433 2021/08 [Refereed][Not invited]
  • 乳房専用超音波CTにおける高精細音速像の有用性(第2報)
    加藤 扶美, 佐藤 恵美, 西田 睦, 山下 啓子, 竹下 卓志, 萩尾 加奈子, 押野 智博, 亀田 浩之, 常田 慧徳, 堀江 達則, 寺田 崇秀, 坪田 悠史, 川畑 健一, 田中 宏樹, 工藤 與亮
    日本乳癌学会総会プログラム抄録集 (一社)日本乳癌学会 29回 72 - 72 2021/07
  • Yutaka Hoshino, Minako Sugiyama, Kenji Hirata, Shohei Honda, Hitoshi Saito, Atsushi Manabe, Kohsuke Kudo
    Acta Radiologica Open 10 (7) 205846012110268 - 205846012110268 2058-4601 2021/07 [Refereed][Not invited]
     
    Commonly, physiological 18F-fluorodeoxyglucose (FDG) uptake in the brain can be observed in 18F-FDG positron emission tomography. Abnormal uptake of 18F-FDG in the brain suggests disorders of central nervous system. Here, we present a case of extremely low 18F-FDG uptake in the brain of a 4-year-old girl with whole-body metastatic neuroblastoma. Almost missing of physiological 18F-FDG uptake in the brain was ascribed at least partly to the metastatic neuroblastoma. The brain could regain physiological 18F-FDG uptake after chemotherapy.
  • Hirokazu Komoriyama, Kiwamu Kamiya, Yuta Kobayashi, Satonori Tsuneta, Takao Konishi, Takuma Sato, Hiroyuki Iwano, Toshiyuki Nagai, Satoru Wakasa, Kohsuke Kudo, Toshihisa Anzai
    Circulation Journal 85 (6) 954 - 954 1346-9843 2021/05/25 [Refereed][Not invited]
  • Yuki Oe, Hiraku Kameda, Hiroshi Nomoto, Keita Sakamoto, Takeshi Soyama, Kyu Yong Cho, Akinobu Nakamura, Daisuke Abo, Kohsuke Kudo, Tatsuya Atsumi, Hideaki Miyoshi
    Journal of the Endocrine Society 5 (Supplement_1) A194 - A194 2021/05/03 
    Abstract Background: Fibroblast growth factor 23 (FGF23) decreases serum phosphate levels by inhibiting proximal tubular phosphate reabsorption and intestinal phosphate absorption by decreasing serum 1,25-dihydroxyvitamin D level, thereby regulating phosphate metabolism. Tumor-induced osteomalacia (TIO) is a rare paraneoplastic syndrome caused by FGF23 overproduction by tumor tissue. Resecting the responsible tumor is a radical treatment for TIO. When the responsible tumor is undetectable, phosphate and active vitamin D administration is recommended. However, supplementation alone is frequently insufficient to maintain phosphate levels and it is difficult to prevent the complications associated with medical therapy, including hypercalciuria and nephrocalcinosis. Recently, burosumab, a human monoclonal anti-FGF23 antibody, has been approved in Japan as a therapeutic agent for FGF23-related hypophosphatemia. Here, we present a patient with TIO effectively treated with burosumab in the absence of identification of tumour location. Clinical case: A 47-year-old female developed pain and edema of the feet; however, the cause could not be determined at local hospitals. Afterwards, she developed marked bone atrophy in the feet and was referred to our hospital. Her age at symptom onset, hypophosphatemia (serum P, 1.9 mg/dl, 2.7 mg/dl &lt; n &lt; 4.6 mg/dl), high serum FGF23 level (630 pg/ml, 16 pg/ml &lt; n &lt; 69 pg/ml), and decreased 1,25-dihydroxyvitamin D level (12.9 pg/ml, 20 pg/ml &lt; n &lt; 60 pg/ml) indicated FGF23-related osteomalacia. She was not having any medication at the time of diagnosis, including saccharified iron oxide or iron polymaltose. Urinary phosphate excretion increased without renal tubular defect; therefore, hypophosphatemic osteomalacia was diagnosed. MRI showed high signal intensity in the talus, sacral, and L5 vertebral regions, indicating multiple pseudofractures. Comprehensive imaging studies, including systemic CT scan and 111In-pentetreotide scintigraphy, did not reveal any tumors despite the suspicion of TIO. Next, we performed systemic venous sampling, which revealed high FGF23 level in the left external iliac vein. Second venous sampling limited to the left lower limb exhibited high FGF23 level in the posterior tibial vein. However, an additional imaging study limited to the left foot could not identify any tumors. Genetic variation was negative for potentially responsible genes, including PHEX and FGF23. We decided to administer burosumab to normalize serum phosphate level without phosphate supplementation. Within 2 months, pain was relieved and the visual analog scale scores also improved from 10 to 6. Moreover, bone MRI showed improved pseudofractures. Conclusion: Burosumab administration was effective for TIO of unknown origin, and it improved not only laboratory findings but also clinical symptoms in this case.
  • Satonori Tsuneta, Noriko Oyama-Manabe, Kenji Hirata, Taisuke Harada, Tadao Aikawa, Osamu Manabe, Hiroshi Ohira, Kazuhiro Koyanagawa, Masanao Naya, Kohsuke Kudo
    Japanese Journal of Radiology 39 (5) 442 - 450 1867-1071 2021/05 [Refereed][Invited]
  • Kenji Hirata, Osamu Manabe, Keiichi Magota, Sho Furuya, Tohru Shiga, Kohsuke Kudo
    Frontiers in Medicine 8 2021/04/28 [Refereed][Not invited]
     
    Background: Diagnostic reports contribute not only to the particular patient, but also to constructing massive training dataset in the era of artificial intelligence (AI). The maximum standardized uptake value (SUVmax) is often described in daily diagnostic reports of [18F] fluorodeoxyglucose (FDG) positron emission tomography (PET) – computed tomography (CT). If SUVmax can be used as an identifier of lesion, that would greatly help AI interpret diagnostic reports. We aimed to clarify whether the lesion can be localized using SUVmax strings. Methods: The institutional review board approved this retrospective study. We investigated a total of 112 lesions from 30 FDG PET-CT images acquired with 3 different scanners. SUVmax was calculated from DICOM files based on the latest Quantitative Imaging Biomarkers Alliance (QIBA) publication. The voxels showing the given SUVmax were exhaustively searched in the whole-body images and counted. SUVmax was provided with 5 different degrees of precision: integer (e.g., 3), 1st decimal places (DP) (3.1), 2nd DP (3.14), 3rd DP (3.142), and 4th DP (3.1416). For instance, when SUVmax = 3.14 was given, the voxels with 3.135 ≤ SUVmax &lt; 3.145 were extracted. We also evaluated whether local maximum restriction could improve the identifying performance, where only the voxels showing the highest intensity within some neighborhood were considered. We defined that “identical detection” was achieved when only single voxel satisfied the criterion. Results: A total of 112 lesions from 30 FDG PET-CT images were investigated. SUVmax ranged from 1.3 to 49.1 (median = 5.6). Generally, when larger and more precise SUVmax values were given, fewer voxels satisfied the criterion. The local maximum restriction was very effective. When SUVmax was determined to 4 decimal places (e.g., 3.1416) and the local maximum restriction was applied, identical detection was achieved in 33.3% (lesions with SUVmax &lt; 2), 79.5% (2 ≤ SUVmax &lt; 5), and 97.8% (5 ≤ SUVmax) of lesions. Conclusion: In this preliminary study, SUVmax of FDG PET-CT could be used as an identifier to localize the lesion if precise SUVmax is provided and local maximum restriction was applied, although the lesions showing SUVmax &lt; 2 were difficult to identify. The proposed method may have potential to make use of diagnostic reports retrospectively for constructing training datasets for AI.
  • 小児領域における他診療科との合同手術 先天性門脈体循環シャントに対するIVR・外科治療戦略
    本多 昌平, 荒 桃子, 奥村 一慶, 近藤 享史, 河北 一誠, 後藤 了一, 阿保 大介, 工藤 與亮, 嶋村 剛, 神山 俊哉, 武冨 紹信
    日本外科学会定期学術集会抄録集 (一社)日本外科学会 121回 WS - 5 2021/04
  • Type 3大動脈弓模型の3分枝へのカテーテライゼーション(Catheterization into branches of simplified type 3 arch models)
    曽山 武士, 今井 哲秋, 吉野 裕紀, 高橋 文也, 森田 亮, 阿保 大介, 吉田 大介, 東海林 菊太郎, 長内 俊也, 工藤 與亮
    日本インターベンショナルラジオロジー学会雑誌 36 (Suppl.) 159 - 159 1340-4520 2021/04
  • 肺動静脈奇形に対する4D flow MRIによる血流評価の実行可能性に関する検討
    阿保 大介, 常田 慧徳, 曽山 武士, 森田 亮, 吉野 裕紀, 高橋 文也, 工藤 與亮
    日本インターベンショナルラジオロジー学会雑誌 (一社)日本インターベンショナルラジオロジー学会 36 (Suppl.) 167 - 167 1340-4520 2021/04
  • 肝エキノコックス症による門脈狭窄に対しバルーン拡張型カバードステントを留置した1例
    山崎 康之, 阿保 大介, 森田 亮, 吉野 裕紀, 高橋 文也, 曽山 武士, 工藤 與亮
    日本インターベンショナルラジオロジー学会雑誌 (一社)日本インターベンショナルラジオロジー学会 36 (Suppl.) 222 - 222 1340-4520 2021/04
  • 胃静脈瘤に対する経皮経門脈的塞栓術の経験
    高橋 文也, 阿保 大介, 曽山 武士, 森田 亮, 吉野 裕紀, 山崎 康之, 曽々木 昇, 宮本 憲幸, 工藤 與亮
    日本インターベンショナルラジオロジー学会雑誌 (一社)日本インターベンショナルラジオロジー学会 36 (Suppl.) 223 - 223 1340-4520 2021/04
  • 血管モデルによる術前シミュレーションを併用したpreloading coil in plug法での腎AVF塞栓術の1例
    森田 亮, 阿保 大介, 曽山 武士, 高橋 文也, 吉野 裕紀, 山崎 康之, 常田 慧徳, 今井 哲秋, 工藤 與亮
    日本インターベンショナルラジオロジー学会雑誌 (一社)日本インターベンショナルラジオロジー学会 36 (Suppl.) 241 - 241 1340-4520 2021/04
  • 開放創部の術後リンパ漏に対しリンパ管塞栓術が有効であった一例(Glue in open wound directly confirmed with intranodal glue embolization for groin lymphorrhea)
    曽々木 昇, 森田 亮, 山崎 康之, 阿保 大介, 曽山 武士, 高橋 文也, 吉野 裕紀, 工藤 與亮
    日本インターベンショナルラジオロジー学会雑誌 36 (Suppl.) 254 - 254 1340-4520 2021/04
  • Akiko Takeuchi, Hideki Hyodoh, Kotaro Matoba, Manabu Murakami, Kohsuke Kudo, Kazuyuki Minowa
    Oral Radiology 38 (1) 29 - 36 0911-6028 2021/03/20 [Refereed][Not invited]
     
    OBJECTIVES: Obstructive sleep apnea syndrome (OSAS) induces upper airway occlusion and may cause sudden death during sleep. This study sought to clarify the relationship between oral air space volume and OSAS onset, which is influenced by multiple factors, such as jawbone, dentition morphology, and oral soft-tissue volume. METHODS: (1) 50 subjects from deceased cases were divided into two groups: OSAS (25 subjects) and controls (25 subjects). (2) 28 subjects from clinical cases were divided into two groups: OSAS (9 subjects) and controls (19 subjects). In all cases, the Computed Tomography (CT) images of the facial region were obtained, and four parameters of oral area volume were analyzed in deceased and clinical cases, and comparisons and analyses were performed between OSAS and control cases. In addition, the efficiency of measurement of these parameters was evaluated using Receiver Operating Characteristic (ROC) curves in OSAS. RESULTS: (1) In deceased cases, oral soft-tissue volume (OSV), oral air-space volume (OAV), and the ratio of OAV to OSV (%air) showed a significant correlation. (2) In clinical cases, OAV and %air showed a significant correlation. In both postmortem and clinical images, a small %air value indicates a high risk of developing OSAS and a high probability of OSAS-related sudden death. CONCLUSIONS: It was shown that the %air is an index to evaluate OSAS by CT imaging of the oral region. OSAS may be indicated when the %air value is ≦ 16.0% in deceased cases and ≦ 6.6% in clinical cases.
  • 巨大乳腺腺筋上皮腫の1例 MRI所見を中心に
    竹中 淳規, 加藤 扶美, 富岡 伸元, 桑原 健, 渡邊 史郎, 坂井 亙, 鈴木 宏明, 高橋 將人, 南部 敏和, 工藤 與亮
    北海道放射線医学雑誌 (NPO)メディカルイメージラボ 1 12 - 17 2021/03 
    症例は50歳代女性。右乳房腫瘤を主訴に前医を受診し、生検で腺筋上皮腫が疑われ、当院乳腺外科受診。MRIでは右乳腺をほぼ置換する腫瘤を認め、早期濃染と洗い出しを示し、嚢胞変性を疑う造影不良域を認めた。拡散強調像で軽度高信号を示し、ADC値は1.264×10^-3mm2/secであった。周囲に小腫瘤やnon-mass enhancementを多数認めた。MRI上、悪性を否定できず、右乳房全摘術が施行された。組織像では腺筋上皮腫と考えられ、明らかな悪性とする異型は認めなかった。主腫瘤の周囲には連続性の不明瞭な腫瘤や不整形病変も見られMRIでの分布に概ね一致していた。乳腺腺筋上皮腫は組織学的に腺上皮細胞と筋上皮細胞がともに増殖を示す極めて稀な良性腫瘍で、画像所見は非特異的で、術前診断は難しい。外科的に切除されるが、局所再発しやすい為、十分なマージンが必要となる。本症例のように腫瘍が広範に存在し、不連続な分布を呈する場合もあり、MRIで病変の範囲を評価することが重要である。(著者抄録)
  • 横田 隼一, 清水 智弘, 坂本 圭太, 清水 幸衣, 浅野 毅, 高橋 大介, 工藤 與亮, 岩崎 倫政
    日本整形外科学会雑誌 (公社)日本整形外科学会 95 (3) S968 - S968 0021-5325 2021/03
  • 全身MRI・骨シンチを用いた特発性大腿骨頭壊死症患者の多発骨壊死の評価
    横田 隼一, 清水 智弘, 坂本 圭太, 清水 幸衣, 中村 夢志郎, 高橋 要, 浅野 毅, 高橋 大介, 工藤 與亮, 岩崎 倫政
    日本リウマチ学会北海道・東北支部学術集会抄録集 (一社)日本リウマチ学会-北海道・東北支部 30回 57 - 57 2021/02
  • Osamu Manabe, Shigeru Yamaguchi, Kenji Hirata, Kentaro Kobayashi, Hiroyuki Kobayashi, Shunsuke Terasaka, Takuya Toyonaga, Keiichi Magota, Yuji Kuge, Nagara Tamaki, Tohru Shiga, Kohsuke Kudo
    Diagnostics 11 (2) 189 - 189 2021/01/28 [Refereed][Not invited]
     
    Background: Positron emission tomography with 11C-methionine (MET) is well established in the diagnostic work-up of malignant brain tumors. Texture analysis is a novel technique for extracting information regarding relationships among surrounding voxels, in order to quantify their inhomogeneity. This study evaluated whether the texture analysis of MET uptake has prognostic value for patients with glioma. Methods: We retrospectively analyzed adults with glioma who had undergone preoperative metabolic imaging at a single center. Tumors were delineated using a threshold of 1.3-fold of the mean standardized uptake value for the contralateral cortex, and then processed to calculate the texture features in glioma. Results: The study included 42 patients (median age: 56 years). The World Health Organization classifications were grade II (7 patients), grade III (17 patients), and grade IV (18 patients). Sixteen (16.1%) all-cause deaths were recorded during the median follow-up of 18.8 months. The univariate analyses revealed that overall survival (OS) was associated with age (hazard ratio (HR) 1.04, 95% confidence interval (CI) 1.01–1.08, p = 0.0093), tumor grade (HR 3.64, 95% CI 1.63–9.63, p = 0.0010), genetic status (p < 0.0001), low gray-level run emphasis (LGRE, calculated from the gray-level run-length matrix) (HR 2.30 × 1011, 95% CI 737.11–4.23 × 1019, p = 0.0096), and correlation (calculated from the gray-level co-occurrence matrix) (HR 5.17, 95% CI 1.07–20.93, p = 0.041). The multivariate analyses revealed OS was independently associated with LGRE and correlation. The survival curves were also significantly different (both log-rank p < 0.05). Conclusion: Textural features obtained using preoperative MET positron emission tomography may compliment the semi-quantitative assessment for prognostication in glioma cases.
  • Noriyuki Fujima, Yukie Shimizu, Daisuke Yoshida, Satoshi Kano, Takatsugu Mizumachi, Akihiro Homma, Koichi Yasuda, Rikiya Onimaru, Osamu Sakai, Kohsuke Kudo, Hiroki Shirato
    The journal of medical investigation : JMI 68 (3.4) 354 - 361 2021 
    Purpose : To predict local control / failure by a multiparametric approach using magnetic resonance (MR)-derived tumor morphological and functional parameters in pharynx squamous cell carcinoma (SCC) patients. Materials and Methods : Twenty-eight patients with oropharyngeal and hypopharyngeal SCCs were included in this study. Quantitative morphological parameters and intratumoral characteristics on T2-weighted images, tumor blood flow from pseudo-continuous arterial spin labeling, and tumor diffusion parameters of three diffusion models from multi-b-value diffusion-weighted imaging as well as patients' characteristics were analyzed. The patients were divided into local control / failure groups. Univariate and multiparametric analysis were performed for the patient group division. Results : The value of morphological parameter of 'sphericity' and intratumoral characteristic of 'homogeneity' was revealed respectively significant for the prediction of the local control status in univariate analysis. Higher diagnostic performance was obtained with the sensitivity of 0.8, specificity of 0.75, positive predictive value of 0.89, negative predictive value of 0.6 and accuracy of 0.79 by multiparametric diagnostic model compared to results in the univariate analysis. Conclusion : A multiparametric analysis with MR-derived quantitative parameters may be useful to predict local control in pharynx SCC patients. J. Med. Invest. 68 : 354-361, August, 2021.
  • 横田 隼一, 清水 智弘, 浅野 毅, 高橋 大介, 岩崎 倫政, 坂本 圭太, 清水 幸衣, 工藤 與亮
    北海道整形災害外科学会雑誌 北海道整形災害外科学会 63 (139th suppl) 92 - 92 1343-3873 2021
  • Kazutaka Harashima, Shiro Watanabe, Nanase Okazaki, Daisuke Endo, Yuko Uchiyama, Fumi Kato, Kenji Hirata, Kohsuke Kudo
    Asia Oceania journal of nuclear medicine & biology 9 (2) 183 - 187 2021 [Refereed][Not invited]
     
    Although 18F-fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) is an established method for the staging of malignancies, benign lesions (e.g, active inflammatory lesions) often show increased metabolic activity. Herpes zoster is the clinical manifestation of the activation and replication of dormant varicella-zoster virus (VZV) in individuals with decreased cell-mediated immunity. Although the diagnosis of herpes zoster is clinical, it is sometimes observed incidentally during imaging for another disease. We describe the case of a 67-year-old Japanese female patient diagnosed with cervical cancer in whom FDG-PET/CT revealed herpes zoster manifestations: hypermetabolic cutaneous lesions in the buttock and pelvic lymph node involvement. The resected lymph nodes showed no malignant lesions but revealed lymphoid follicle formation, probably related to viral infection. There has been no report comparing FDG-PET findings of lymph nodes with histologic findings; the present findings are compatible with a clinically VZV-induced inflammatory reaction in regional lymph nodes, which increased FDG accumulation. Active infection with VZV displays increased FDG uptake in regional lymph nodes and may lead to incorrect malignant disease management in oncology. Misdiagnoses can be avoided by a careful interpretation by experienced nuclear medicine physicians as well as proper clinical evaluation.
  • Kosuke Otsuka, Kiyoshi Egawa, Noriyuki Fujima, Kohsuke Kudo, Satoshi Terae, Midori Nakajima, Tomoshiro Ito, Kazuyori Yagyu, Hideaki Shiraishi
    Epilepsy & Behavior 114 (Pt A) 107516 - 107516 1525-5050 2021/01 [Refereed][Not invited]
     
    OBJECTIVE: This study examined whether the application of magnetoencephalography (MEG) to interpret magnetic resonance imaging (MRI) findings can aid the diagnosis of intractable epilepsy caused by organic brain lesions. METHODS: This study included 51 patients with epilepsy who had MEG clusters but whose initial MRI findings were interpreted as being negative for organic lesions. Three board-certified radiologists reinterpreted the MRI findings, utilizing the MEG findings as a guide. The degree to which the reinterpretation of the imaging results identified an organic lesion was rated on a 5-point scale. RESULTS: Reinterpretation of the MRI data with MEG guidance helped detect an abnormality by at least one radiologist in 18 of the 51 patients (35.2%) with symptomatic localization-related epilepsy. A surgery was performed in 7 of the 51 patients, and histopathological analysis results identified focal cortical dysplasia in 5 patients (Ia: 1, IIa: 2, unknown: 2), hippocampal sclerosis in 1 patient, and dysplastic neurons/gliosis in 1 patient. CONCLUSIONS: The results of this study highlight the potential diagnostic applications of MEG to detect organic epileptogenic lesions, particularly when radiological visualization is difficult with MRI alone.
  • Ryo Morita, Daisuke Abo, Takeshi Soyama, Yuki Yoshino, Toru Yoshikawa, Tasuku Kimura, Kohsuke Kudo
    CVIR Endovascular 3 (1) 37 - 37 2020/12 [Refereed][Not invited]
     
    Abstract Background Vascular abnormalities in neurofibromatosis type 1 (NF1) are rare, but are the second leading cause of death in persons with NF1. In NF1 vasculopathy (NF-V), fatal bleeding due to a spontaneous arterial rupture sometimes occurs. Ruptured extracranial arteries in patients with NF1 often involve thoracic vessels, such as the intercostal and subclavian arteries; very few reports exist regarding the abdominal region. Herein, we present the first case of intraperitoneal bleeding due to spontaneous pancreatic arcade artery (PAA) rupture associated with NF1, successfully treated by transcatheter arterial embolization (TAE) combined with stent-graft placement and partial intra-aortic balloon occlusion (IABO). Case presentation A 40-year-old woman complained of back and abdominal pain. Upon admission, her blood pressure was 85/41 mmHg and heart rate was 129 beats/min. Computed tomography (CT) showed large intraperitoneal bleeding due to PAA rupture. After CT scanning, her systolic blood pressure decreased to 50 mmHg. Therefore, we performed emergency TAE with partial IABO. She was treated by TAE of the anterior superior pancreaticoduodenal artery, anterior inferior pancreaticoduodenal artery, and inferior pancreaticoduodenal artery. However, even after TAE, minor extravasation around the superior mesenteric artery continued, and her vital signs remained unstable. Stent-graft placement was selected to stop the haemorrhage, preserving normal blood flow of the superior mesenteric artery trunk. Excellent patency of the stent graft was confirmed on follow-up CT, and she was discharged on postoperative day 56. Conclusion PAA rupture associated with NF1 can be successfully treated by TAE combined with partial intra-aortic balloon occlusion, and stent-graft placement.
  • Keiichi Magota, Naoto Numata, Daiki Shinyama, Junya Katahata, Yamato Munakata, Piotr J. Maniawski, Kentaro Kobayashi, Osamu Manabe, Kenji Hirata, Ukihide Tateishi, Kohsuke Kudo, Tohru Shiga
    EJNMMI Physics 7 (1) 66 - 66 2020/12 [Refereed][Not invited]
     
    Abstract Background Halo artifacts from urinary catheters can occur due to inaccurate scatter correction, and the artifacts affect the tumor visibility in 18F-FDG PET/CT images. We investigated the incidence rate and the mechanisms of halo-artifact generation and explored several scatter correction techniques to prevent artifacts. Methods We conducted patient and phantom studies. (1) We retrospectively reviewed the cases of patients who had undergone 18F-FDG PET/CT scans. To determine the frequency of halo-artifact generation, we used the patients’ PET images with a standard scatter correction based on a tail-fitted single-scatter simulation (TF-SSS) using 4-mm voxel μ-maps (TFS 4-mm). (2) We performed phantom studies to evaluate the effects of a urine catheter and two scatter correction techniques, i.e., TF-SSS with 2-mm voxel μ-maps (TFS 2-mm) and a Monte Carlo-based single-scatter simulation (MC-SSS) using 4-mm voxel μ-maps (MCS 4-mm). The average standardized uptake values (SUVs) were measured for axial PET images. (3) Using the patients’ data, we investigated whether TFS 2-mm and MCS 4-mm can eliminate the artifacts in the clinical images. Results (1) There were 61 patients with urinary catheters; in five (8.2%), halo artifacts were observed in the TFS 4-mm PET images. (2) The phantom study clearly reproduced the halo artifacts in the TFS 4-mm PET images. The halo artifacts were generated when urine moved in the interval between the CT and PET imaging, and when the urinary catheter was placed in a circular shape. The SUVs for the TFS 4-mm and TFS-2mm PET images were underestimated at the halo-artifact regions, whereas the SUVs for the MCS 4-mm PET images were close to the true values. (3) The halo artifacts disappeared in the TFS 2-mm PET images in 4/5 patients but not 1/5 patient, whereas the halo artifacts were completely absent in the MCS 4-mm PET images in 5/5 patients. Conclusions These data suggest that halo artifacts are caused if the PET images do not correspond to the physical material in the μ-maps, which induces the scatter correction error. With the MC-SSS, it was possible to accurately estimate the scatter without generating halo artifacts.
  • Masahito Takagi, Kanta Tanaka, Kaori Miwa, Makoto Sasaki, Masatoshi Koga, Teruyuki Hirano, Kenji Kamiyama, Yoshiki Yagita, Yoshinari Nagakane, Haruhiko Hoshino, Tadashi Terasaki, Yusuke Yakushiji, Kohsuke Kudo, Masafumi Ihara, Sohei Yoshimura, Yoshitaka Yamaguchi, Masayuki Shiozawa, Kazunori Toyoda
    European Stroke Journal 5 (4) 423 - 431 2396-9873 2020/12 [Refereed][Not invited]
     
    Aims The bleeding risk of current antithrombotic strategies in clinical settings, including recently developed agents, needs to be clarified. Methods and Design In an investigator-initiated, prospective, multicentre, observational study, patients with cerebrovascular or cardiovascular diseases who were taking oral antiplatelet or anticoagulant agents were enrolled. Compulsory multimodal magnetic resonance images were acquired at baseline to assess cerebral small vessel disease. Six-month follow-up will be performed for two years. The primary outcome is major bleeding as defined by the International Society on Thrombosis and Hemostasis. Results Between October 2016 and March 2019, 5306 patients (71.7 ± 11.2 years old, 1762 women) were enrolled. Previous intracranial haemorrhage was documented in 181 patients (3.4%), cerebrovascular disease (including asymptomatic) requiring antithrombotic therapy in 5006 patients (94.3%), and atrial fibrillation in 1061 patients (20.0%). At entry, 3726 patients (70.2%) were taking antiplatelet agents alone, including 551 (10.4%) using dual antiplatelet agents, 1317 (24.8%) taking anticoagulants alone, and the remaining 263 (5.0%) taking both. The leading antiplatelet agent was clopidogrel (2014 patients), and the leading combination of dual antiplatelet medication was clopidogrel plus aspirin (362). Use of direct oral anticoagulants (1029 patients, 19.4%) exceeded warfarin use (554, 10.4%). The number of pivotal bleeding events exceeded 200 in April 2020. Conclusions This study is expected to provide the incidence of bleeding complications of recent oral antithrombotics in clinical practice and identify their associations with underlying small vessel disease and other biomarkers. Novel risk stratification models for bleeding risk will be able to be created based on the study results.
  • Ryo Morita, Daisuke Abo, Yusuke Sakuhara, Takeshi Soyama, Norio Katoh, Naoki Miyamoto, Yuusuke Uchinami, Shinichi Shimizu, Hiroki Shirato, Kohsuke Kudo
    Minimally Invasive Therapy & Allied Technologies 29 (6) 334 - 343 1364-5706 2020/12/01 [Refereed][Not invited]
     
    Purpose: This study evaluated the success rate and complications of percutaneous implantation of hepatic fiducial true-spherical gold markers for real-time adaptive radiotherapy (RAR), which constitutes real-time image-guided radiotherapy with gating.Material and methods: We retrospectively evaluated 100 patients who underwent 116 percutaneous intrahepatic implantations of 2-mm-diameter, spherical, gold fiducial markers before RAR from 1999 to 2016, with Seldinger's method. We defined technical success as marker placement at the intended liver parenchyma, without mispositioning, and clinical success as successful tracking of the gold marker and completion of planned RAR. Complications related to marker placement were assessed.Results: The technical success rate for true-spherical gold marker implantation was 92.2% (107/116). Nine of 116 markers migrated (intra-procedurally in seven patients, delayed in two patients). Migration out of the liver (n = 4) or intrahepatic vessels (n = 5) occurred without complications; these markers were not retrieved. The clinical success rate was 100.0% (115/115). Abdominal pain occurred in 16 patients, fever and hemorrhage in seven patients each, and pneumothorax and nausea in one patient each. No major complications were encountered.Conclusions: Percutaneous transhepatic implantation of true-spherical gold markers for RAR is feasible and can be conducted with a high success rate and low complication rate.
  • 竹中 淳規, 山口 晃典, 原田 太以佑, 工藤 與亮, 高桑 恵美, 山口 秀
    画像診断 (株)学研メディカル秀潤社 40 (14) 1394 - 1395 0285-0524 2020/11
  • 乳房専用超音波CTの初期使用経験 高精細音速像の有用性
    加藤 扶美, 山下 啓子, 佐藤 恵美, 西田 睦, 竹下 卓志, 萩尾 加奈子, 押野 智博, 亀田 浩之, 常田 慧徳, 堀江 達則, 寺田 崇秀, 坪田 悠史, 川畑 健一, 工藤 與亮
    日本乳癌学会総会プログラム抄録集 (一社)日本乳癌学会 28回 144 - 144 2020/10
  • 大江 悠希, 亀田 啓, 家坂 光, 泉原 里美, 上垣 里紗, 亀田 玲奈, 野本 博司, 坂本 圭太, 曽山 武士, 曹 圭龍, 中村 昭伸, 阿保 大介, 工藤 與亮, 三好 秀明, 渥美 達也
    日本内分泌学会雑誌 (一社)日本内分泌学会 96 (2) 529 - 529 0029-0661 2020/10
  • PTGBD後に心肺停止に至った大量胆道出血の1例
    曽々木 昇, 高橋 文也, 吉野 裕紀, 森田 亮, 曽山 武士, 阿保 大介, 工藤 與亮
    日本医学放射線学会秋季臨床大会抄録集 (公社)日本医学放射線学会 56回 S145 - S145 0048-0428 2020/10
  • 阿保 大介, 曽山 武士, 森田 亮, 高橋 文也, 吉野 裕紀, 工藤 與亮
    日本外科感染症学会雑誌 (一社)日本外科感染症学会 17 (5) 365 - 365 1349-5755 2020/10
  • 乳房専用超音波CTの初期使用経験 高精細音速像の有用性
    加藤 扶美, 山下 啓子, 佐藤 恵美, 西田 睦, 竹下 卓志, 萩尾 加奈子, 押野 智博, 亀田 浩之, 常田 慧徳, 堀江 達則, 寺田 崇秀, 坪田 悠史, 川畑 健一, 工藤 與亮
    日本乳癌学会総会プログラム抄録集 (一社)日本乳癌学会 28回 144 - 144 2020/10
  • Satonori Tsuneta, Daisuke Abo, Noriko Oyama-Manabe, Chihoko Miyazaki, Yuki Yoshino, Ryo Morita, Takeshi Soyama, Kohsuke Kudo
    CardioVascular and Interventional Radiology 43 (10) 1557 - 1560 0174-1551 2020/10 [Refereed][Not invited]
  • Daisuke Sawamura, Hisashi Narita, Naoki Hashimoto, Shin Nakagawa, Hiroyuki Hamaguchi, Noriyuki Fujima, Kohsuke Kudo, Hiroki Shirato, Khin K Tha
    Journal of magnetic resonance imaging : JMRI 52 (4) 1187 - 1196 2020/10 [Refereed][Not invited]
     
    BACKGROUND: Identifying structural and functional abnormalities in bipolar (BD) and major depressive disorders (MDD) is important for understanding biological processes. HYPOTHESIS: Diffusion kurtosis imaging (DKI) may be able to detect the brain's microstructural alterations in BD and MDD and any differences between the two. STUDY TYPE: Prospective. SUBJECTS: In all, 16 BD patients, 19 MDD patients, and 20 age- and gender-matched healthy volunteers. FIELD STRENGTH/SEQUENCE: DKI at 3.0T. ASSESSMENT: The major DKI indices of the brain were compared voxel-by-voxel among the three groups. Significantly different voxels were tested for correlation with clinical variables (ie, Young Mania Rating Scale [YMRS], 17-item Hamilton Depression Rating Scale [17-HDRS], Montgomery-Åsberg Depression Rating Scale, total disease duration, duration of current episode, and the number of past manic/depressive episodes). The performance of the DKI indices in identifying microstructural alterations was estimated. STATISTICAL TESTS: One-way analysis of variance (ANOVA) was used for group comparison of DKI indices. The performance of these indices in detecting microstructural alterations was determined by receiver operating characteristic (ROC) analysis. Pearson's product-moment correlation analyses were used to test the correlations of these indices with clinical variables. RESULTS: DKI revealed widespread microstructural alterations across the brain in each disorder (P < 0.05). Some were significantly different between the two disorders. Mean kurtosis (MK) in the gray matter of the right inferior parietal lobe was able to distinguish BD and MDD with an accuracy of 0.906. A strong correlation was revealed between MK in that region and YMRS in BD patients (r = -0.641, corrected P = 0.042) or 17-HDRS in MDD patients (r = -0.613, corrected P = 0.030). There were also strong correlations between a few other DKI indices and disease duration (r = -0.676 or 0.626, corrected P < 0.05). DATA CONCLUSION: DKI detected microstructural brain alterations in BD and MDD. Its indices may be useful to distinguish the two disorders or to reflect disease severity and duration. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY STAGE: 3 J. Magn. Reson. Imaging 2020;52:1187-1196.
  • 原嶋 十考, 中川 純一, 原田 太以佑, 坂本 圭太, 工藤 與亮, 中里 信一, 清水 亜衣
    画像診断 (株)学研メディカル秀潤社 40 (12) 1158 - 1159 0285-0524 2020/09
  • Yuan-Hao Lee, Swee Tian Quek, Pek-Lan Khong, Cindy S. Lee, Jim S. Wu, Lei Zhang, Kwan-Hoong Ng, Seoung-Oh Yang, Kohsuke Kudo, Kyung-Hyun Do, Seung Hyup Kim, Dillon C. Chen, Amy Cheng, Joseph Hang Leung, Yeun-Chung Chang, Hsian-He Hsu, Wing P. Chan
    The British Journal of Radiology 93 (1113) 20200082 - 20200082 0007-1285 2020/09 [Refereed][Not invited]
     
    Objective: To understand the status of pre-procedural safety practices in radiological examinations at radiology residency training institutions in various Asian regions. Methods: A questionnaire based on the Joint Commission International Accreditation Standards was electronically sent to 3 institutions each in 10 geographical regions across 9 Asian countries. Questions addressing 45 practices were divided into 3 categories. A five-tier scale with numerical scores was used to evaluate safety practices in each institution. Responses obtained from three institutions in the United States were used to validate the execution rate of each surveyed safety practice. Results: The institutional response rate was 70.0% (7 Asian regions, 21 institutions). 44 practices (all those surveyed except for the application of wrist tags for identifying patients with fall risks) were validated using the US participants. Overall, the Asian participants reached a consensus on 89% of the safety practices. Comparatively, most Asian participants did not routinely perform three pre-procedural practices in the examination appropriateness topic. Conclusion: Based on the responses from 21 participating Asian institutions, most routinely perform standard practices during radiological examinations except when it comes to examination appropriateness. This study can provide direction for safety policymakers scrutinizing and improving regional standards of care. Advances in knowledge: This is the first multicenter survey study to elucidate pre-procedural safety practices in radiological examinations in seven Asian regions.
  • 巨大骨盤AVMに対する塞栓術の治療効果を4D-flow MRIにより定量的に評価できた一例(Quantitative evaluation of a giant pelvic arteriovenous malformation by 4D-flow MRI: a case report)
    阿保 大介, 常田 慧徳, 真鍋 徳子, 曽山 武士, 森田 亮, 吉野 裕紀, 木野田 直也, 工藤 與亮
    日本インターベンショナルラジオロジー学会雑誌 35 (Suppl.) 179 - 179 1340-4520 2020/08
  • Up-to-7 inのHCC患者において超選択的TACEは選択的TACEに対しsurvival benefitを有するか?
    吉野 裕紀, 阿保 大介, 森田 亮, 曽山 武士, 工藤 與亮
    日本インターベンショナルラジオロジー学会雑誌 (一社)日本インターベンショナルラジオロジー学会 35 (Suppl.) 192 - 192 1340-4520 2020/08
  • 子宮動静脈奇形に対し動脈塞栓術併用経静脈的塞栓術を施行した1例
    森田 亮, 阿保 大介, 木野田 直也, 曽山 武士, 吉野 裕紀, 常田 慧徳, 工藤 與亮
    日本インターベンショナルラジオロジー学会雑誌 (一社)日本インターベンショナルラジオロジー学会 35 (Suppl.) 217 - 217 1340-4520 2020/08
  • 子宮動脈-卵巣動脈吻合枝領域からの出血をNBCAで塞栓した1例
    渡辺 祈一, 森田 亮, 阿保 大介, 曽山 武士, 吉野 裕紀, 木野田 直也, 加藤 扶美, 桜井 康雄, 児玉 芳尚, 工藤 與亮
    日本インターベンショナルラジオロジー学会雑誌 (一社)日本インターベンショナルラジオロジー学会 35 (Suppl.) 219 - 219 1340-4520 2020/08
  • 外腸骨動脈破裂を来たした子宮頸癌治療後難治性腸管穿孔の1例
    木野田 直也, 森田 亮, 阿保 大介, 曽山 武士, 吉野 裕紀, 工藤 與亮, 野崎 綾子, 加藤 達矢, 渡利 英道
    日本インターベンショナルラジオロジー学会雑誌 (一社)日本インターベンショナルラジオロジー学会 35 (Suppl.) 246 - 246 1340-4520 2020/08
  • 肺動静脈奇形に対し卵円孔経由で経静脈的塞栓術を施行した1例
    阿保 大介, 曽山 武士, 永井 利幸, 森田 亮, 吉野 裕紀, 木野田 直也, 工藤 與亮
    日本インターベンショナルラジオロジー学会雑誌 (一社)日本インターベンショナルラジオロジー学会 35 (Suppl.) 216 - 216 1340-4520 2020/08
  • 巨大骨盤AVMに対する塞栓術の治療効果を4D-flow MRIにより定量的に評価できた一例(Quantitative evaluation of a giant pelvic arteriovenous malformation by 4D-flow MRI: a case report)
    阿保 大介, 常田 慧徳, 真鍋 徳子, 曽山 武士, 森田 亮, 吉野 裕紀, 木野田 直也, 工藤 與亮
    日本インターベンショナルラジオロジー学会雑誌 35 (Suppl.) 179 - 179 1340-4520 2020/08
  • Up-to-7 inのHCC患者において超選択的TACEは選択的TACEに対しsurvival benefitを有するか?
    吉野 裕紀, 阿保 大介, 森田 亮, 曽山 武士, 工藤 與亮
    日本インターベンショナルラジオロジー学会雑誌 (一社)日本インターベンショナルラジオロジー学会 35 (Suppl.) 192 - 192 1340-4520 2020/08
  • 肺動静脈奇形に対し卵円孔経由で経静脈的塞栓術を施行した1例
    阿保 大介, 曽山 武士, 永井 利幸, 森田 亮, 吉野 裕紀, 木野田 直也, 工藤 與亮
    日本インターベンショナルラジオロジー学会雑誌 (一社)日本インターベンショナルラジオロジー学会 35 (Suppl.) 216 - 216 1340-4520 2020/08
  • 子宮動静脈奇形に対し動脈塞栓術併用経静脈的塞栓術を施行した1例
    森田 亮, 阿保 大介, 木野田 直也, 曽山 武士, 吉野 裕紀, 常田 慧徳, 工藤 與亮
    日本インターベンショナルラジオロジー学会雑誌 (一社)日本インターベンショナルラジオロジー学会 35 (Suppl.) 217 - 217 1340-4520 2020/08
  • 子宮動脈-卵巣動脈吻合枝領域からの出血をNBCAで塞栓した1例
    渡辺 祈一, 森田 亮, 阿保 大介, 曽山 武士, 吉野 裕紀, 木野田 直也, 加藤 扶美, 桜井 康雄, 児玉 芳尚, 工藤 與亮
    日本インターベンショナルラジオロジー学会雑誌 (一社)日本インターベンショナルラジオロジー学会 35 (Suppl.) 219 - 219 1340-4520 2020/08
  • 外腸骨動脈破裂を来たした子宮頸癌治療後難治性腸管穿孔の1例
    木野田 直也, 森田 亮, 阿保 大介, 曽山 武士, 吉野 裕紀, 工藤 與亮, 野崎 綾子, 加藤 達矢, 渡利 英道
    日本インターベンショナルラジオロジー学会雑誌 (一社)日本インターベンショナルラジオロジー学会 35 (Suppl.) 246 - 246 1340-4520 2020/08
  • 曽々木 昇, 志村 亮祐, 原田 太以佑, 工藤 與亮, 清水 亜衣, 松野 吉宏
    画像診断 (株)学研メディカル秀潤社 40 (9) 902 - 903 0285-0524 2020/07
  • Kentaro Kobayashi, Osamu Manabe, Kenji Hirata, Shigeru Yamaguchi, Hiroyuki Kobayashi, Shunsuke Terasaka, Takuya Toyonaga, Sho Furuya, Keiichi Magota, Yuji Kuge, Kohsuke Kudo, Tohru Shiga, Nagara Tamaki
    European Journal of Nuclear Medicine and Molecular Imaging 47 (8) 1833 - 1842 1619-7070 2020/07 [Refereed][Not invited]
     
    PURPOSE: 18F-fluoromisonidazole (18F-FMISO) is the most widely used positron emission tomography (PET) tracer for imaging tumor hypoxia. Previous reports suggested that the time from injection to the scan may affect the assessment of 18F-FMISO uptake. Herein, we directly compared the images at 2 h and 4 h after a single injection of 18F-FMISO. METHODS: Twenty-three patients with or suspected of having a brain tumor were scanned twice at 2 and 4 h following an intravenous injection of 18F-FMISO. We estimated the mean standardized uptake value (SUV) of the gray matter and white matter and the gray-to-white matter ratio in the background brain tissue from the two scans. We also performed a semi-quantitative analysis using the SUVmax and maximum tumor-to-normal ratio (TNR) for the tumor. RESULTS: At 2 h, the SUVmean of gray matter was significantly higher than that of white matter (median 1.23, interquartile range (IQR) 1.10-1.32 vs. 1.04, IQR 0.95-1.16, p < 0.0001), whereas at 4 h, it significantly decreased to approach that of the white matter (1.10, IQR 1.00-1.23 vs. 1.02, IQR 0.93-1.13, p = NS). The gray-to-white matter ratio thus significantly declined from 1.17 (IQR 1.14-1.19) to 1.09 (IQR 1.07-1.10) (p < 0.0001). All 7 patients with glioblastoma showed significant increases in the SUVmax (2.20, IQR 1.67-3.32 at 2 h vs. 2.65, IQR 1.74-4.41 at 4 h, p = 0.016) and the TNR (1.75, IQR 1.40-2.38 at 2 h vs. 2.34, IQR 1.67-3.60 at 4 h, p = 0.016). CONCLUSION: In the assessment of hypoxic tumors, 18F-FMISO PET for hypoxia imaging should be obtained at 4 h rather than 2 h after the injection.
  • Satonori Tsuneta, Noriko Oyama-Manabe, Hiroyuki Kameda, Taisuke Harada, Fumi Kato, Ewoud J. Smit, Mathias Prokop, Kohsuke Kudo
    Medicine 99 (26) e20804 - e20804 0025-7974 2020/06/26 [Refereed][Not invited]
     
    The aim of this study was to evaluate the effect of a novel 4-dimensional similarity filter (4DSF) on quantitative and qualitative parameters of low-dose dynamic myocardial computed tomography perfusion (CTP) images.In this retrospective study, medical records of 32 patients with suspected or known coronary artery disease who underwent dynamic myocardial CTP at 80 kV were included. The 4DSF reduces noise by averaging voxels that have similar dynamic behavior after adaptive iterative dose reduction 3D (AIDR3D) and deformable image registration were applied. Qualitative (artefact, contour sharpness, and myocardial homogeneity [1 = poor; 2 = intermediate; 3 = good]) and quantitative measurement (standard deviation [SD] and signal-to-noise ratio [SNR]) were compared between the 4DSF and AIDR3D. Contrast-to-noise ratio (CNR) between ischemic and normal remote myocardium was also assessed using myocardial perfusion magnetic resonance imaging as the reference standard in seven patients.The 4DSF was successfully applied to all the images. Improvement in subjective image quality yielded by 4DSF was higher than that yielded by AIDR3D (homogeneity, 1.0 [3 vs 2]; artefact, 1.5 [3 vs 1.5]; P < .001) in all patients. The 4DSF significantly decreased the SD by 59% (AIDR3D vs 4DSF: 33.5 ± 0.4 vs 13.8 ± 0.4, P < .001), increased the SNR by 134% (AIDR3D vs 4DSF: 4.4 ± 0.2 vs 10.3 ± 0.2, P < .001), and increased the CNR by 131% (AIDR3D vs 4DSF: 1.6 ± 0.2 vs 3.7 ± 0.2, P < .001).The 4DSF improved the qualitative and quantitative parameters of low-dose dynamic myocardial CTP images.
  • 井浦 孝紀, 吉川 仁人, 原田 太以佑, 工藤 與亮, 清水 亜衣, 松野 吉宏
    画像診断 (株)学研メディカル秀潤社 40 (8) 776 - 777 0285-0524 2020/06 
    <文献概要>症例は10歳代,男性.息苦しさと左胸痛を自覚,胸部単純X線写真(非提示)で縦隔腫瘍が疑われた.造影CTでは,前縦隔に12cm大の境界明瞭で分葉状形態を示す腫瘤を認め,内部は不均一な造影効果を示し,不整形な石灰化が散見された他,脂肪の吸収値を示す小構造が認められた.MRIでは,T2強調像で大部分は不均一な高信号を示し,大小の嚢胞成分を伴っていた.また,脂肪抑制T1強調像で病変の一部に地図状の高信号域を認め,出血が疑われた.腫瘍マーカーは,hCG-β 131.1mIU/ml(正常値<0.5mIU/ml),AFP 9077.7ng/ml(1.0〜10.0ng/ml)といずれも異常高値であった.以上の画像所見および臨床情報から,混合型胚細胞腫瘍を強く疑った.なお,精巣には腫大や左右差を認めなかった.
  • Noriyuki Fujima, Hiroyuki Kameda, Yukie Shimizu, Taisuke Harada, Khin Khin Tha, Masami Yoneyama, Kohsuke Kudo
    Magnetic resonance imaging 69 81 - 87 2020/06 [Refereed][Not invited]
     
    PURPOSE: To investigate the utility of diffusion-weighted arterial spin labeling (DW-ASL) for detecting the progression of brain white matter lesions. MATERIALS AND METHODS: A total of 492 regions of interest (ROIs) in 41 patients were prospectively analyzed. DW-ASL was performed using the diffusion gradient prepulse of five b-values (0, 25, 60, 102, and 189) before the ASL readout. We calculated the water exchange rate (Kw) with post-processing using the ASL signal information for each b-value. The cerebral blood flow (CBF) was also calculated using b0 images. Using the signal information in FLAIR (fluid-attenuated inversion recovery) images, we classified the severity of white matter lesions into three grades: non-lesion, moderate, and severe. In addition, the normal Kw level was measured from DW-ASL data of 60 ROIs in five control subjects. The degree of variance of the Kw values (Kw-var) was calculated by squaring the value of the difference between each Kw value and the normal Kw level. All patient's ROIs were divided into non-progressive and progressive white matter lesions by comparing the present FLAIR images with those obtained 2 years before this acquisition. RESULTS: Compared to the non-progressive group, the progressive group had significantly lower CBF, significantly higher severity grades in FLAIR, and significantly greater Kw-var values. In a receiver operator characteristic curve analysis, a high area under the curve (AUC) of 0.89 was obtained with the use of Kw-var. In contrast, the AUCs of 0.59 for CBF and 0.72 for severity grades in FLAIR were obtained. CONCLUSIONS: The DW-ASL technique can be useful to detect the progression of brain white matter lesions. This technique will become a clinical tool for patients with various degrees of white matter lesions.
  • T Shima, N Fujima, S Yamano, K Kudo, K Hirata, K Minowa
    Clinical radiology 75 (5) 397.e15-397.e21  2020/05 [Refereed][Not invited]
     
    AIM: To evaluate and compare diffusion-weighted imaging (DWI) parameters derived from a non-Gaussian fitting model and positron-emission tomography (PET) parameters derived from 18F-fluoromisonidazole-PET (FMISO-PET) in patients with oral squamous cell carcinoma (OSCC). MATERIALS AND METHODS: Primary sites were evaluated prospectively in 18 patients. DWI was performed using six b-values (0-2,500). Diffusion-related parameters of kurtosis value (K), the kurtosis-corrected diffusion coefficient (DK), diffusion heterogeneity (α), distributed diffusion coefficient (DDC), the slow diffusion coefficient (Dslow), and the apparent diffusion coefficient (ADC) were calculated from four diffusion-fitting models. Maximal standardised uptake values (SUVmax), mean standardised uptake values (SUVmean), and the tumour-to-muscle ration (TMR) of the SUV value were calculated for FMISO-PET. Spearman's correlation coefficient was used to evaluate the correlation between each non-Gaussian diffusion model parameters and PET parameter. RESULTS: There was moderate correlation between FMISO-PET SUVmax and Dslow (ρ=-0.45, p=0.06). In addition, there was good correlation between TMRmax and five non-Gaussian diffusion model parameters (K: ρ=0.65, p=0.004, DK: ρ=-0.72, p=0.0008, DDC: ρ=-0.75, p=0.0003, ADC: ρ=-0.74, p=0.0005, and Dslow: ρ= -0.65, p=0.003), and between TMRmean and five non-Gaussian model parameters (K: ρ=0.64, p=0.005, DK: ρ=-0.61, p=0.007, DDC: ρ=-0.63, p=0.005, ADC: ρ=-0.61, p=0.007, and Dslow: ρ=-0.56, p=0.015). CONCLUSION: Non-Gaussian diffusion model parameters can be related to tumour hypoxia.
  • TAEにて良好な骨形成を得た術後残存動脈瘤様骨嚢腫の1例
    吉河 亨, 森田 亮, 阿保 大介, 吉野 裕紀, 曽山 武士, 工藤 與亮, 新井 隆太, 木村 輔
    日本インターベンショナルラジオロジー学会雑誌 (一社)日本インターベンショナルラジオロジー学会 34 (4) 296 - 296 1340-4520 2020/04
  • 膵アーケード破裂に対しVIABAHN留置を施行した神経線維腫症1型の1例
    森田 亮, 阿保 大介, 吉野 裕紀, 曽山 武士, 工藤 與亮, 木村 輔, 上石 崇史
    日本インターベンショナルラジオロジー学会雑誌 (一社)日本インターベンショナルラジオロジー学会 34 (4) 297 - 297 1340-4520 2020/04
  • 尿管ステント抜去による総腸骨動脈尿管瘻に対しVIABAHN留置を施行した1例
    木野田 直也, 阿保 大介, 曽山 武士, 森田 亮, 吉野 裕紀, 工藤 與亮, 松本 隆児, 安部 崇重, 篠原 信雄
    日本インターベンショナルラジオロジー学会雑誌 (一社)日本インターベンショナルラジオロジー学会 34 (4) 297 - 297 1340-4520 2020/04
  • コイル塞栓術における先端可動型マイクロカテーテルの先端ロック機構の有用性の基礎的検討
    阿保 大介, 曽山 武士, 森田 亮, 吉野 裕紀, 工藤 與亮, 上石 崇史, 金谷 本真, 高柳 歩, 山崎 康之
    日本インターベンショナルラジオロジー学会雑誌 (一社)日本インターベンショナルラジオロジー学会 34 (4) 299 - 299 1340-4520 2020/04
  • 腹部領域のコイル塞栓術におけるマイクロカテーテルTACTICSの初期使用経験
    吉野 裕紀, 阿保 大介, 森田 亮, 曽山 武士, 木野田 直也, 吉河 亨, 工藤 與亮
    日本インターベンショナルラジオロジー学会雑誌 (一社)日本インターベンショナルラジオロジー学会 34 (4) 299 - 299 1340-4520 2020/04
  • 超選択的CDDP-TACEとEpi-Lip-TACEによりCRに至った門脈腫瘍栓を伴う肝細胞癌術後再発の1例
    曽山 武士, 阿保 大介, 吉野 裕紀, 森田 亮, 工藤 與亮, 長津 明久, 折茂 達也, 島田 慎吾, 蒲池 浩文, 神山 俊哉, 木村 輔, 横尾 英樹
    日本インターベンショナルラジオロジー学会雑誌 (一社)日本インターベンショナルラジオロジー学会 34 (4) 295 - 295 1340-4520 2020/04
  • Ryosuke Shimura, Toshiya Osanai, Kohsuke Kudo
    No shinkei geka. Neurological surgery 48 (4) 295 - 306 2020/04 [Not refereed][Invited]
  • 小脳型多系統萎縮症におけるプロトン密度強調画像を用いた小脳の信号強度の検討
    山口 晃典, 原田 太以佑, 工藤 與亮, 松島 理明, 矢部 一郎, 佐々木 秀直
    Japanese Journal of Radiology (公社)日本医学放射線学会 38 (Suppl.) 1 - 1 1867-1071 2020/02
  • Somatic malignant transformationが疑われたgerm cell tumor再発の1例
    高柳 歩, 原田 太以佑, 藤間 憲幸, 工藤 與亮, 岡田 宏美, 山口 秀, 小林 浩之
    Japanese Journal of Radiology (公社)日本医学放射線学会 38 (Suppl.) 7 - 7 1867-1071 2020/02
  • Morita Ryo, Abo Daisuke, Soyama Takeshi, Takahashi Bunya, Yoshino Yuki, Yamasaki Koji, Kudo Kohsuke
    The Official Journal of the Japanese Society of Interventional Radiology 一般社団法人日本インターベンショナルラジオロジー学会 35 (2) 113 - 126 1340-4520 2020 
    Post-operative complications such as abdominal fluid collection, abscess, bile leakage (BL) and pancreatic fistula (PF) can occur after hepato-biliary pancreatic surgery. Effective drainage is essential for these post-operative complications. Here, we describe non-vascular IR techniques for post-operative complications after hepato-biliary pancreatic surgery, showing our cases.
  • 藤間 憲幸, 清水 幸衣, 工藤 與亮
    画像診断 (株)学研メディカル秀潤社 40 (2) 180 - 189 0285-0524 2020/01 
    <文献概要>Point ・脳腫瘍や脱髄・炎症疾患はMRI撮像プロトコールの幅が非常に広く,検査目的に応じてその内容を吟味する必要がある.・病態や疾患によって一般的な撮像法だけでなく,特殊撮像法がより有用となる場面があるため,その適応を熟知すべきである.・標的病変の形態や局在に応じて,冠状断像や矢状断像の追加,あるいは3D収集の利用を常に念頭に置いて,撮像内容を決定すべきである.
  • Masatoshi Koga, Manabu Inoue, Kazutaka Sonoda, Kanta Tanaka, Masayuki Shiozawa, Takashi Okada, Hajime Ikenouchi, Tetsuya Fukuda, Tetsu Satow, Masafumi Ihara, Ryo Itabashi, Kohsuke Kudo, Hiroshi Yamagami, Kazunori Toyoda
    Japanese Journal of Stroke 42 (6) 495 - 501 0912-0726 2020
  • Yukie Shimizu, Kohsuke Kudo, Hiroyuki Kameda, Taisuke Harada, Noriyuki Fujima, Takuya Toyonaga, Khin Khin Tha, Hiroki Shirato
    Magnetic Resonance in Medical Sciences 19 (3) 227 - 234 1347-3182 2020 [Refereed][Not invited]
  • Sho Furuya, Masanao Naya, Osamu Manabe, Kenji Hirata, Hiroshi Ohira, Tadao Aikawa, Kazuhiro Koyanagawa, Keiichi Magota, Ichizo Tsujino, Toshihisa Anzai, Yuji Kuge, Noriko Oyama-Manabe, Kohsuke Kudo, Tohru Shiga, Nagara Tamaki
    Journal of nuclear cardiology : official publication of the American Society of Nuclear Cardiology 28 (5) 2141 - 2148 2019/12/09 [Refereed][Not invited]
     
    BACKGROUND: 18F-fluoromisonidazole (FMISO) is a hypoxia positron emission tomography (PET) tracer. Here, we evaluated cardiac and extra-cardiac sarcoidosis using both FMISO and 18F-fluorodeoxyglucose (FDG) PET/CT in a prospective cohort of patients with sarcoidosis. METHODS: Ten consecutive sarcoidosis patients with suspected cardiac involvement were prospectively enrolled. Each patient fasted overnight (for ≥ 18 hours) preceded by a low-carbohydrate diet before FDG PET/CT but not given special dietary instructions before the FMISO PET/CT scan. We visually and semiquantitatively assessed the uptakes of FMISO and FDG using the maximal standardized uptake value (SUVmax). The metabolic volume (MV) of FDG was calculated as the volume within the boundary determined by the threshold (mean SUV of blood pool × 1.5). RESULTS: Nine patients showed focal FDG uptake in the myocardium and were diagnosed with cardiac sarcoidosis. Among the patients with extra-cardiac lesions, FDG uptake was seen in 8 lymph nodes and 3 lung lesions. FMISO uptake was seen in the 7 cardiac (77.8%) and 6 extra-cardiac (54.5%) lesions. None of the patients showed physiological FMISO uptake in the myocardium. The SUVmax values of the lesions with FMISO uptake were higher than those of the lesions without FMISO uptake in both the cardiac (SUVmax: 9.9, IQR: 8.4-10.0 vs 7.3, IQR: 6.3-8.2) and non-cardiac lesions (SUVmax: 17.6, IQR: 14.5-19.3 vs 6.1, IQR: 5.9-6.2; P = 0.006). The MV values of the lesions with FMISO uptake were significantly higher than those of the lesions without FMISO uptake (111.3, IQR: 78.3-135.7 vs 6.4, IQR: 1.9-23.3; P = 0.0009). CONCLUSIONS: FMISO showed no physiological myocardial uptake and did not require special preparation. FMISO PET has the potential to detect hypoxic lesions in patients with sarcoidosis.
  • 当科におけるViabahnの初期使用経験
    小泉 富基, 阿保 大介, 曽山 武士, 森田 亮, 吉野 裕紀, 木村 輔, 工藤 與亮
    日本インターベンショナルラジオロジー学会雑誌 (一社)日本インターベンショナルラジオロジー学会 34 (2) 160 - 160 1340-4520 2019/12
  • メラノーマ腹膜播種に対してBland TAEを施行している1例
    金谷 本真, 阿保 大介, 吉野 裕紀, 木村 輔, 曽山 武士, 森田 亮, 工藤 與亮
    日本インターベンショナルラジオロジー学会雑誌 (一社)日本インターベンショナルラジオロジー学会 34 (2) 161 - 161 1340-4520 2019/12
  • 抜去困難となった埋め込み型中心静脈カテーテルをpull-throughとcoaxial snare techniqueを用いて経皮的に除去した1例
    吉野 裕紀, 曽山 武士, 木村 輔, 森田 亮, 阿保 大介, 工藤 與亮
    日本インターベンショナルラジオロジー学会雑誌 (一社)日本インターベンショナルラジオロジー学会 34 (2) 163 - 163 1340-4520 2019/12
  • 【肝胆膵の救急疾患とその最新の治療現場】肝胆膵領域疾患への新しいmodality 腹部領域IVRでの先端可動型マイクロカテーテルの有用性
    阿保 大介, 曽山 武士, 森田 亮, 吉野 裕紀, 工藤 與亮
    肝胆膵 (株)アークメディア 79 (4) 769 - 778 0389-4991 2019/10
  • MRI構造画像と磁化率画像に基づくアルツハイマー病の診断指標
    佐藤 良太, 工藤 與亮, 河田 康雄, 宇土 仁木, 松島 理明, 矢部 一郎, 山口 晃典, 尾藤 良孝, 越智 久晃, 白猪 亨
    Dementia Japan (一社)日本認知症学会 33 (4) 553 - 553 1342-646X 2019/10
  • 阿保 大介, 曽山 武士, 森田 亮, 吉野 裕紀, 工藤 與亮
    日本外科感染症学会雑誌 (一社)日本外科感染症学会 16 (5) 510 - 510 1349-5755 2019/10
  • 新しい塞栓物質とデバイスの登場によるBRTOの新たな展開 AZUR CX35を駆使したBRTO
    吉野 裕紀, 阿保 大介, 森田 亮, 曽山 武士, 木野田 直也, 工藤 與亮
    日本門脈圧亢進症学会雑誌 (一社)日本門脈圧亢進症学会 25 (3) 91 - 91 1344-8447 2019/09
  • Fumi Kato, Kohsuke Kudo, Hiroko Yamashita, Motoi Baba, Ai Shimizu, Noriko Oyama-Manabe, Rumiko Kinoshita, Ruijiang Li, Hiroki Shirato
    Breast cancer (Tokyo, Japan) 26 (5) 628 - 636 1340-6868 2019/09 [Refereed][Not invited]
     
    BACKGROUND: We investigated the usefulness of the minimum ADC value of primary breast lesions for predicting axillary lymph node (LN) status in luminal A-like breast cancers with clinically negative nodes in comparison with the mean ADC. METHODS: Forty-four luminal A-like breast cancers without axillary LN metastasis at preoperative clinical evaluation, surgically resected with sentinel LN biopsy, were retrospectively studied. Mean and minimum ADC values of each lesion were measured and statistically compared between LN positive (n = 12) and LN negative (n = 32) groups. An ROC curve was drawn to determine the best cutoff value to differentiate LN status. Correlations between mean and minimum ADC values and the number of metastatic axillary LNs were investigated. RESULTS: Mean and minimum ADC values of breast lesions with positive LN were significantly lower than those with negative LN (mean 839.9 ± 110.9 vs. 1022.2 ± 250.0 × 10- 6 mm2/s, p = 0.027, minimum 696.7 ± 128.0 vs. 925.0 ± 257.6 × 10- 6 mm2/s, p = 0.004). The sensitivity and NPV using the best cutoff value from ROC using both mean and minimum ADC were 100%. AUC of the minimum ADC (0.784) was higher than that of the mean ADC (0.719). Statistically significant negative correlations were observed between both mean and minimum ADCs and number of positive LNs, with stronger correlation to minimum ADC than mean ADC. CONCLUSIONS: The minimum ADC value of primary breast lesions predicts axillary LN metastasis in luminal A-like breast cancer with clinically negative nodes, with high sensitivity and high NPV.
  • Mari Miyata, Shingo Kakeda, Kohsuke Kudo, Shigeru Iwata, Yoshiya Tanaka, Yi Wang, Yukunori Korogi
    Journal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism 39 (8) 1648 - 1658 2019/08 [Refereed][Not invited]
     
    The purposes of this study are to assess the oxygen extraction fraction (OEF) changes on MRI-based quantitative susceptibility mapping (QSM) in systemic lupus erythematosus (SLE) patients and to determine whether QSM-OEF is associated with disease activity in SLE. We enrolled 42 SLE patients and 20 healthy subjects (HS) who had no pathologies on conventional brain MRI. Disease activity was assessed using SLE Disease Activity Index (SLEDAI). For the measurement of QSM-OEF, QSM data were analysed using the Perfusion Mismatch Analyzer software program. Spearman's or Pearson's correlation coefficients were calculated, and independent predictors were identified through a multiple linear regression analysis. QSM-OEF was significantly higher in SLE than that in HS (51.3 ± 10.1 vs. 40.5 ± 3.7, p < 0.001). QSM-OEF was positively correlated with SLEDAI and the presence of neuropsychiatric symptom (NPS) scores (ρ = 0.663, p < 0.001 and ρ = 0.340, p = 0.028). At multiple linear regression analysis, SLEDAI and NPS were independently associated with QSM-OEF (standardized β = 0.426, p = 0.016 and standardized β = 6.148, p = 0.029). In the SLE patients, QSM-OEF is associated with disease activity, which might predict an increased risk of stroke in SLE.
  • Noriyuki Fujima, Yukie Shimizu, Daisuke Yoshida, Satoshi Kano, Takatsugu Mizumachi, Akihiro Homma, Koichi Yasuda, Rikiya Onimaru, Osamu Sakai, Kohsuke Kudo, Hiroki Shirato
    Cancers 11 (6) 2019/06/10 [Refereed][Not invited]
     
    The purpose of this study was to determine the predictive power for treatment outcome of a machine-learning algorithm combining magnetic resonance imaging (MRI)-derived data in patients with sinonasal squamous cell carcinomas (SCCs). Thirty-six primary lesions in 36 patients were evaluated. Quantitative morphological parameters and intratumoral characteristics from T2-weighted images, tumor perfusion parameters from arterial spin labeling (ASL) and tumor diffusion parameters of five diffusion models from multi-b-value diffusion-weighted imaging (DWI) were obtained. Machine learning by a non-linear support vector machine (SVM) was used to construct the best diagnostic algorithm for the prediction of local control and failure. The diagnostic accuracy was evaluated using a 9-fold cross-validation scheme, dividing patients into training and validation sets. Classification criteria for the division of local control and failure in nine training sets could be constructed with a mean sensitivity of 0.98, specificity of 0.91, positive predictive value (PPV) of 0.94, negative predictive value (NPV) of 0.97, and accuracy of 0.96. The nine validation data sets showed a mean sensitivity of 1.0, specificity of 0.82, PPV of 0.86, NPV of 1.0, and accuracy of 0.92. In conclusion, a machine-learning algorithm using various MR imaging-derived data can be helpful for the prediction of treatment outcomes in patients with sinonasal SCCs.
  • 原田 太以佑, 工藤 與亮, 亀田 浩之, 佐藤 良太, 白猪 亨, 尾藤 良孝, 藤間 憲幸, 常田 慧徳, 野川 敏史, 前田 憲一郎, 林 宏至, 佐々木 真理
    日本磁気共鳴医学会雑誌 (一社)日本磁気共鳴医学会 39 (2) 66 - 66 0914-9457 2019/05
  • 術後合併症救済に役立つnon-vascular IVR(Non-vascular IVR for salvage of post-operative complications)
    阿保 大介, 曽山 武士, 森田 亮, 吉野 裕紀, 木村 輔, 工藤 與亮
    日本インターベンショナルラジオロジー学会雑誌 34 (Suppl.) 165 - 165 1340-4520 2019/05
  • コイル塞栓術における先端可動型マイクロカテーテルの先端ロック機構の有用性の基礎的検討
    阿保 大介, 曽山 武士, 森田 亮, 上石 崇史, 金谷 本真, 高柳 歩, 山崎 康之, 吉野 裕紀, 木村 輔, 工藤 與亮
    日本インターベンショナルラジオロジー学会雑誌 (一社)日本インターベンショナルラジオロジー学会 34 (Suppl.) 307 - 307 1340-4520 2019/05
  • Kaori Endo, Masahiko Takahata, Hiroyuki Sugimori, Satoshi Yamada, Shigeru Tadano, Jeffrey Wang, Masahiro Todoh, Yoichi M Ito, Daisuke Takahashi, Kohsuke Kudo, Norimasa Iwasaki
    Clinical biomechanics (Bristol, Avon) 65 13 - 18 0268-0033 2019/05 [Refereed][Not invited]
     
    BACKGROUND: Since bone mass is not the only determinant of bone strength, there has been increasing interest in incorporating the bone quality into fracture risk assessments. We aimed to examine whether the magnetic resonance imaging (MRI) T1 or T2 mapping value could provide information that is complementary to bone mineral density for more accurate prediction of cancellous bone strength. METHODS: Four postmenopausal women with hip osteoarthritis underwent 3.0-T MRI to acquire the T1 and T2 values of the cancellous bone of the femoral head before total hip arthroplasty. After the surgery, the excised femoral head was portioned into multiple cubic cancellous bone specimens with side of 5 mm, and the specimens were then subjected to microcomputed tomography followed by biomechanical testing. FINDINGS: The T1 value positively correlated with the yield stress (σy) and collapsed stress (σc). The T2 value did not correlate with the yield stress, but it correlated with the collapsed stress and strength reduction ratio (σc/σy), which reflects the progressive re-fracture risk. Partial correlation coefficient analyses, after adjusting for the bone mineral density, showed a statistically significant correlation between T1 value and yield stress. The use of multiple coefficients of determination by least squares analysis emphasizes the superiority of combining the bone mineral density and the MRI mapping values in predicting the cancellous bone strength compared with the bone mineral density-based prediction alone. INTERPRETATION: The MRI T1 and T2 values predict cancellous bone strength including the change in bone quality.
  • Suzuko Aoike, Hiroyuki Sugimori, Noriyuki Fujima, Yuriko Suzuki, Yukie Shimizu, Akira Suwa, Kinya Ishizaka, Kohsuke Kudo
    Magnetic resonance in medical sciences : MRMS : an official journal of Japan Society of Magnetic Resonance in Medicine 18 (2) 170 - 177 1347-3182 2019/04/10 [Refereed][Not invited]
     
    We evaluated 3D pseudo-continuous arterial spin labeling (pCASL) using turbo spin echo with a pseudo-steady-state (PSS) readout in comparison with the other major readout methods of 3D spiral and 2D echo-planar imaging (EPI). 3D-PSS produced cerebral blood flow (CBF) values well correlated to those of the 3D spiral readout. By visual evaluation, the image quality of 3D-PSS pCASL was superior to that of 2D-EPI. The 3D-PSS technique was suggested useful as pCASL readout.
  • Yasuka Kikuchi, Masanao Naya, Noriko Oyama-Manabe, Osamu Manabe, Hiroyuki Sugimori, Kohsuke Kudo, Fumi Kato, Tadao Aikawa, Hiroyuki Tsutsui, Nagara Tamaki, Hiroki Shirato
    Magnetic resonance in medical sciences : MRMS : an official journal of Japan Society of Magnetic Resonance in Medicine 18 (2) 134 - 141 1347-3182 2019/04/10 [Refereed][Not invited]
     
    PURPOSE: The aim of this study was to verify coronary flow velocity reserve (CFVR) on the left main trunk (LMT) in comparison with myocardial flow reserve (MFR) by 15O-labeled water positron emission tomography (PET) (MFR-PET) in both the healthy adults and the patients with coronary artery disease (CAD), and to evaluate the feasibility of CFVR to detect CAD. METHODS: Eighteen healthy adults and 13 patients with CAD were evaluated. CFVR in LMT was estimated by 3T magnetic resonance imaging (MRI) with phase contrast technique. MFR-PET in the LMT territory including anterior descending artery and circumflex artery was calculated as the ratio of myocardial blood flow (MBF)-PET at stress to MBF-PET at rest. RESULTS: There was a significant positive relationship between CFVR and MFR-PET (R = 0.45, P < 0.0001). Inter-observer calculations of CFVR showed good correlation (R2 = 0.93, P < 0.0001). The CFVR in patients with CAD was significantly lower than that in healthy adults (1.90 ± 0.61 vs. 2.77 ± 1.03, respectively, P = 0.01), which were similar to the results of MFR-PET (2.23 ± 0.84 vs. 3.96 ± 1.04, respectively, P < 0.0001). For the detection of patients with CAD, the area under the curve was 0.78 (P = 0.01). The sensitivity was 0.77 and specificity was 0.72 when a cut-off of 2.15 was used. CONCLUSION: CFVR by 3T was validated with MFR-PET. CFVR could detect the patients with CAD. This method is a simple and reliable index without radiation or contrast material.
  • Coil TAEにおけるSteerable microcatheterの有用性
    阿保 大介, 曽山 武士, 森田 亮, 吉野 裕紀, 木村 輔, 工藤 與亮
    日本インターベンショナルラジオロジー学会雑誌 (一社)日本インターベンショナルラジオロジー学会 33 (4) 422 - 422 1340-4520 2019/04
  • 消化管出血に対してIPM/CSを用いたTAEが奏功した1例
    金谷 本真, 阿保 大介, 曽山 武士, 森田 亮, 吉野 裕紀, 木村 輔, 工藤 與亮, 川村 典生, 後藤 了一, 渡辺 正明, 嶋村 剛
    日本インターベンショナルラジオロジー学会雑誌 (一社)日本インターベンショナルラジオロジー学会 33 (4) 422 - 423 1340-4520 2019/04
  • 左下横隔動脈経由で還流されていた脾動脈に対しPSEを施行した1例
    木村 輔, 阿保 大介, 吉野 裕紀, 森田 亮, 曽山 武士, 工藤 與亮
    日本インターベンショナルラジオロジー学会雑誌 (一社)日本インターベンショナルラジオロジー学会 33 (4) 423 - 423 1340-4520 2019/04
  • 腎部分切除術後の難治性尿瘻に対し、選択的TAEによる部分腎機能廃絶術が奏功した1例
    吉野 裕紀, 曽山 武士, 森田 亮, 阿保 大介, 木村 輔, 工藤 與亮
    日本インターベンショナルラジオロジー学会雑誌 (一社)日本インターベンショナルラジオロジー学会 33 (4) 426 - 426 1340-4520 2019/04
  • 背部刺傷の1例
    曽山 武士, 阿保 大介, 森田 亮, 吉野 裕紀, 木村 輔, 工藤 與亮, 前川 邦彦, 新垣 雅人, 長津 明久, 若山 顕治
    日本インターベンショナルラジオロジー学会雑誌 (一社)日本インターベンショナルラジオロジー学会 33 (4) 423 - 423 1340-4520 2019/04 [Refereed][Not invited]
  • Noriyuki Fujima, Akihiro Homma, Taisuke Harada, Yukie Shimizu, Khin Khin Tha, Satoshi Kano, Takatsugu Mizumachi, Ruijiang Li, Kohsuke Kudo, Hiroki Shirato
    Cancer imaging : the official publication of the International Cancer Imaging Society 19 (1) 5 - 5 1740-5025 2019/02/04 [Refereed][Not invited]
     
    BACKGROUND: To assess the utility of histogram and texture analysis of magnetic resonance (MR) fat-suppressed T2-weighted imaging (Fs-T2WI) for the prediction of histological diagnosis of head and neck squamous cell carcinoma (SCC) and malignant lymphoma (ML). METHODS: The cases of 57 patients with SCC (45 well/moderately and 12 poorly differentiated SCC) and 10 patients with ML were retrospectively analyzed. Quantitative parameters with histogram features (relative mean signal, coefficient of variation, kurtosis and skewness) and gray-level co-occurrence matrix (GLCM) features (contrast, correlation, energy and homogeneity) were calculated using Fs-T2WI data with a manual tumor region of interest (ROI). RESULTS: The following significantly different values were obtained for the total SCC versus ML groups: relative mean signal (3.65 ± 0.86 vs. 2.61 ± 0.49), contrast (72.9 ± 16.2 vs. 49.3 ± 8.7) and homogeneity (2.22 ± 0.25 × 10- 1 vs. 2.53 ± 0.12 × 10- 1). In the comparison of the SCC histological grades, the relative mean signal and contrast were significantly lower in the poorly differentiated SCC (2.89 ± 0.63, 56.2 ± 12.9) compared to the well/moderately SCC (3.85 ± 0.81, 77.5 ± 13.9). The homogeneity in poorly differentiated SCC (2.56 ± 0.15 × 10- 1) was higher than that of the well/moderately SCC (2.1 ± 0.18 × 10- 1). CONCLUSIONS: Parameters obtained by histogram and texture analysis of Fs-T2WI may be useful for noninvasive prediction of histological type and grade in head and neck malignancy.
  • 特徴的な画像所見を呈した鞍上部immature teratomaの1例
    藤井 宝顕, 原田 太以佑, 清水 幸衣, 藤間 憲幸, Tha Khin Khin, 工藤 與亮, 寺坂 俊介, 長 祐子, 白土 博樹
    Japanese Journal of Radiology (公社)日本医学放射線学会 37 (Suppl.) 4 - 4 1867-1071 2019/02
  • くも膜下出血後にびまん性の白質障害を呈した1例
    古家 翔, 原田 太以佑, 清水 幸衣, 藤間 憲幸, Tha Khin Khin, 工藤 與亮, 月花 正幸, 中山 若樹, 白土 博樹
    Japanese Journal of Radiology (公社)日本医学放射線学会 37 (Suppl.) 10 - 10 1867-1071 2019/02
  • TAE, Coiling, Stenting(TAE, Coiling, Stenting)
    阿保 大介, 曽山 武士, 森田 亮, 吉野 裕紀, 木村 輔, 工藤 與亮
    日本腹部救急医学会雑誌 (一社)日本腹部救急医学会 39 (2) 314 - 314 1340-2242 2019/02
  • IVRで使う最新デバイスと技術秘技 腹部領域のIVRにおける先端可動型マイクロカテーテル(Leonis mova)の有用性
    阿保 大介, 曽山 武士, 森田 亮, 吉野 裕紀, 木村 輔, 工藤 與亮
    日本腹部救急医学会雑誌 (一社)日本腹部救急医学会 39 (2) 336 - 336 1340-2242 2019/02
  • Masahiro Yasaka, Kazuo Minematsu, Kazunori Toyoda, Etsuro Mori, Teruyuki Hirano, Toshimitsu Hamasaki, Hiroshi Yamagami, Takehiko Nagao, Shinichi Yoshimura, Shinichiro Uchiyama, Takenori Yamaguchi, Yasushi Okada, Satoshi Okuda, Kazumi Kimura, Norio Tanahashi, Yasuo Terayama, Yoichiro Hashimoto, Yasuhiro Hasegawa, Kiyohiro Houkin, Masayasu Matsumoto, Kazuo Kitagawa, Masahiro Yasaka, Ken Nagata, Shigeru Nogawa, Yoshiaki Kumon, Takeshi Kimura, Yutaka Furukawa, Tomohiro Sakamoto, Makoto Sakai, Kohsuke Kudo, Toshinori Hirai, Shotai Kobayashi
    PLOS ONE 14 (2) 1932-6203 2019/02 [Refereed][Not invited]
     
    The efficacy of early anticoagulation in acute stroke with nonvalvular atrial fibrillation (NVAF) remains unclear. We performed a study to evaluate the risk of recurrent ischemic stroke (IS) and major bleeding in acute IS patients with NVAF who started rivaroxaban. This observational study evaluated patients with NVAF and acute IS/transient ischemic attack (TIA) in the middle cerebral arterial territory who started rivaroxaban within 30 days after the index IS/TIA. The primary endpoints were recurrent IS and major bleeding within 90 days after the index IS/TIA. The relationship between the endpoints and the time to start rivaroxaban was evaluated by correlation analysis using cerebral infarct volume, determined by diffusion-weighted magnetic resonance images within 48 hours of onset of the index IS/TIA. Of 1309 patients analyzed, recurrent IS occurred in 30 (2.3%) and major bleeding in 11 (0.8%) patients. Among patients with known infarct size (N = 1207), those with small (<4.0 cm(3)), medium (>= 4.0 and <22.5 cm(3)), and large (>= 22.5 cm(3)) infarcts started rivaroxaban a median of 2.9, 2.9, and 5.8 days, respectively, after the index IS/TIA. Recurrent IS was significantly less frequent when starting rivaroxaban <= 14 days versus >= 15 days after IS (2.0% versus 6.8%, P=0.0034). Incidences of recurrent IS and major bleeding in whom rivaroxaban was started <3 days (N = 584) after IS were also low: 1.5% and 0.7%, respectively. Initiation of rivaroxaban administration in acute IS or TIA was associated with a low recurrence of IS (2.3%), and a low incidence of major bleeding events (0.8%) for 90 days after the index stroke. For the prevention of recurrent attacks in acute IS patients with NVAF, it is feasible to start the administration of rivaroxaban within 14 days of onset. Rivaroxaban started within 3 days of onset may be a feasible treatment option for patients with a small or medium-sized infarction.
  • Oyama-Manabe Noriko, Manabe Osamu, Naya Masanao, Kudo Kohsuke, Tamaki Nagara
    Annals of Nuclear Cardiology 日本心臓核医学会 5 (1) 79 - 83 2189-3926 2019 [Refereed][Not invited]
     
    Cardiac computed tomography (CT) could provide the comprehensive morphologic and functional information of coronary artery disease. Coronary CT angiography has been well established for identification and management of symptomatic patients with or suspected coronary artery disease. However, we should know the anatomical stenosis is not the same as the functional one needed to be treated. Dynamic perfusion imaging could lead a non-invasive quantitative evaluation of myocardial ischemia with estimation of myocardial blood flow. In this review, we address the characteristics and advantages of cardiac CT, in particular dynamic perfusion CT for quantitative evaluation of myocardial ischemia.
  • 古家 翔, 原田 太以佑, 清水 幸衣, 藤間 憲幸, Tha Khin Khin, 工藤 與亮, 月花 正幸, 中山 若樹, 白土 博樹
    核医学 (一社)日本核医学会 55 (1) 40 - 40 0022-7854 2018/12
  • N Fujima, K Hirata, T Shiga, R Li, K Yasuda, R Onimaru, K Tsuchiya, S Kano, T Mizumachi, A Homma, K Kudo, H Shirato
    Clinical radiology 73 (12) 1059.e1-1059.e8  2018/12 [Refereed][Not invited]
     
    AIM: To assess potential prognostic factors in pharynx squamous cell carcinoma (SCC) patients by quantitative morphological and intratumoural characteristics obtained by 2-[18F]-fluoro-2-deoxy-d-glucose positron-emission tomography/computed tomography (FDG-PET/CT). MATERIALS AND METHODS: The cases of 54 patients with pharynx SCC who underwent chemoradiation therapy were analysed retrospectively. Using their FDG-PET data, the quantitative morphological and intratumoural characteristics of 14 parameters were calculated. The progression-free survival (PFS) and overall survival (OS) information was obtained from patient medical records. Univariate and multivariate analyses were performed to assess the 14 quantitative parameters as well as the T-stage, N-stage, and tumour location data for their relation to PFS and OS. When an independent predictor was suggested in the multivariate analysis, the parameter was further assessed using the Kaplan-Meier method. RESULTS: In the assessment of PFS, the univariate and multivariate analyses indicated the following as independent predictors: the texture parameter of homogeneity and the morphological parameter of sphericity. In the Kaplan-Meier analysis, the PFS rate was significantly improved in the patients who had both a higher value of homogeneity (p=0.01) and a higher value of sphericity (p=0.002). With the combined use of homogeneity and sphericity, the patients with different PFS rates could be divided more clearly. CONCLUSION: The quantitative parameters of homogeneity and sphericity obtained by FDG-PET can be useful for the prediction of the PFS of pharynx SCC patients, especially when used in combination.
  • Taisuke Harada, Kohsuke Kudo
    Brain and nerve = Shinkei kenkyu no shinpo 70 (12) 1331 - 1340 1881-6096 2018/12 [Not refereed][Invited]
     
    Tremor is one of the common movement disorders encountered in a clinical practice. Tremor is often difficult to diagnose and can be easily mistaken for another disorder, hence diagnostic imaging is employed to provide objective information. The morphometry, signal changes, neuromelanin, and iron deposition can be evaluated by MRI, whereas cardiac sympathetic nerve and dopamine transporter degeneration are detected by means of nuclear medicine. The purpose of this article is to provide an overview of the role and indications of imaging test, as well as a review of the methods in which the findings of images are interpreted.
  • 阿保 大介, 中村 透, 曽山 武士, 森田 亮, 吉野 裕紀, 木村 輔, 金谷 本真, 小泉 富基, 工藤 與亮, 平野 聡
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 33 (3) 229 - 235 1340-4520 2018/11 
    腹腔動脈合併尾側膵切除術(DP-CAR)術前血流改変の目的は、側副血行路を術前に発達させ、術後に予測される胃や肝臓等の虚血性合併症を予防・低減することである。著者らが考案したdual microcatheter-dual interlocking detachable coil technique(DMDI)法を適応する前後の合併症の頻度について比較したところ、DMDI法適応後が有意に合併症が少なかった。1)DP-CARの今までの歴史、2)DP-CARの治療成績、3)DP-CAR術前血流改変、4)DP-CAR術前血流改変の合併症、について概説した。
  • 経皮的直接穿刺及びNBCA注入により治癒し得た膵移植後十二指腸断端漏の1例
    阿保 大介, 曽山 武士, 森田 亮, 加藤 大貴, 吉野 裕紀, 工藤 與亮, 川村 典生, 腰塚 靖之, 後藤 了一, 渡辺 正明, 嶋村 剛
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 33 (3) 311 - 311 1340-4520 2018/11
  • 単一ルートからの胆管内rendezvousを用いて離断PTBDチューブを経皮的に回収した1例
    吉野 裕紀, 曽山 武士, 加藤 大祐, 加藤 大貴, 森田 亮, 阿保 大介, 工藤 與亮
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 33 (3) 311 - 312 1340-4520 2018/11
  • 経皮的腸瘻造設により砕石が可能となった肝内胆管結石の1例
    加藤 大貴, 阿保 大介, 志村 亮佑, 曽山 武士, 森田 亮, 加藤 大祐, 吉野 裕紀, 工藤 與亮, 折茂 達也, 蒲池 浩文, 神山 俊哉
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 33 (3) 312 - 312 1340-4520 2018/11
  • 肺動脈瘤に対しTAEを行った1例
    藤井 宝顕, 阿保 大介, 吉野 裕紀, 曽山 武士, 森田 亮, 加藤 大貴, 工藤 與亮, 篠原 正裕
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 33 (3) 313 - 313 1340-4520 2018/11
  • 左上腕からのPICC先端のZone B留置により上大静脈穿破を来した1例
    曽山 武士, 吉野 裕紀, 森田 亮, 加藤 大貴, 加藤 大祐, 阿保 大介, 工藤 與亮
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 33 (3) 313 - 313 1340-4520 2018/11
  • AVP-1及びcoilを用いて腎AVMのhigh flow feederを塞栓した1例
    吉野 裕紀, 阿保 大介, 森田 亮, 加藤 大貴, 加藤 大祐, 曽山 武士, 工藤 與亮
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 33 (3) 313 - 313 1340-4520 2018/11
  • 子宮・腟出血に対しnon-uterine arteryを塞栓した2例
    山崎 康之, 曽山 武士, 吉野 裕紀, 加藤 大貴, 森田 亮, 阿保 大介, 工藤 與亮
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 33 (3) 314 - 314 1340-4520 2018/11
  • Oyama-Manabe Noriko, Satoshi Yabusaki, Manabe Osamu, Kato Fumi, Kanno-Okada Hiromi, Kudo Kohsuke
    RADIOGRAPHICS 38 (7) 1934 - 1948 0271-5333 2018/11 [Refereed][Invited]
  • 内腸骨動脈閉塞症例に生じた死冠からの出血に対し、難渋しつつもTAEで止血しえた1例
    上石 崇史, 阿保 大介, 曽山 武士, 森田 亮, 吉野 裕紀, 木村 輔, 工藤 與亮
    日本医学放射線学会秋季臨床大会抄録集 (公社)日本医学放射線学会 54回 S551 - S551 0048-0428 2018/09
  • Noriyuki Fujima, Kenji Hirata, Tohru Shiga, Koichi Yasuda, Rikiya Onimaru, Kazuhiko Tsuchiya, Satoshi Kano, Takatsugu Mizumachi, Akihiro Homma, Kohsuke Kudo, Hiroki Shirato
    Quantitative imaging in medicine and surgery 8 (8) 788 - 795 2223-4292 2018/09 [Refereed][Not invited]
     
    Background: To investigate the utility of quantitative morphological and intratumoral characteristics obtained by 18F-fluorodeoxyglucose positron-emission tomography/computed tomography (FDG-PET/CT) for the prediction of treatment outcome in patients with nasal or paranasal cavity squamous cell carcinoma (SCC). Methods: Twenty-four patients with nasal or paranasal cavity SCC who received curative non-surgical therapy (a combination of super-selective arterial cisplatin infusion and radiotherapy) were retrospectively analyzed. From pre-treatment FDG-PET data, a total of 13 parameters of quantitative morphological characteristics (tumor volume, surface area and sphericity), intratumoral characteristics (the maximum and mean standard uptake value, three intratumoral histogram and four textural parameters) and total lesion glycolysis (TLG) were respectively calculated. Information regarding the treatment outcome was determined from the histological diagnosis or clinical follow-up. Each of the 13 quantitative parameters as well as T- and N-stage was assessed for its relation to treatment outcome of local control or failure. Results: In univariate analysis, significant differences in surface area and sphericity between the local control and failure groups were observed. The receiver operating characteristic (ROC) curve analysis showed that sphericity had the highest accuracy of 0.88. In the multivariate analysis, sphericity was revealed as an independent predictor of the local control or failure. Conclusions: The quantitative parameters of sphericity are useful to predict the treatment outcome in patients with nasal or paranasal SCC.
  • 原田 太以佑, 藤間 憲幸, 工藤 與亮
    INNERVISION (株)インナービジョン 33 (9) 37 - 40 0913-8919 2018/08 
    磁化率は組織固有の物理的性質であり、その画像化として磁化率強調画像(susceptibility weighted imaging:SWI)や位相差強調画像(phase difference enhanced imaging:PADRE)が定性画像として用いられている。近年では、MRIを用いた定量化が一つのテーマとなっており、定量的磁化率マッピング(quantitative susceptibility mapping:QSM)は、磁化率を定量的に評価できる方法として、ここ数年で臨床研究の報告が急増している。本稿では、QSMの臨床応用と最近の知見について概説する。(著者抄録)
  • Kohsuke Kudo, Taisuke Harada, Hiroyuki Kameda, Ikuko Uwano, Fumio Yamashita, Satomi Higuchi, Kunihiro Yoshioka, Makoto Sasaki
    Magnetic resonance in medical sciences : MRMS : an official journal of Japan Society of Magnetic Resonance in Medicine 17 (3) 223 - 230 1347-3182 2018/07/10 [Refereed][Not invited]
     
    PURPOSE: The feasibility of steady-state sequences for 17O imaging was evaluated based on a kinetic analysis of the brain parenchyma and cerebrospinal fluid (CSF). MATERIALS AND METHODS: The institutional review board approved this prospective study with written informed consent. Dynamic 2D or 3D steady-state sequences were performed in five and nine participants, respectively, with different parameters using a 3T scanner. During two consecutive dynamic scans, saline was intravenously administered for control purposes in the first scan, and 20% 17O-labeled water (1 mL/Kg) was administered in the second scan. Signal changes relative to the baseline were calculated, and kinetic analyses of the curves were conducted for all voxels. Region of interest analysis was performed in the brain parenchyma, choroid plexus, and CSF spaces. RESULTS: Average signal drops were significantly larger in the 17O group than in the controls for most of the imaging parameters. Different kinetic parameters were observed between the brain parenchyma and CSF spaces. Average and maximum signal drops were significantly larger in the CSF spaces and choroid plexus than in the brain parenchyma. Bolus arrival, time to peak, and the first moment of dynamic curves of 17O in the CSF space were delayed compared to that in the brain parenchyma. Significant differences between the ventricle and subarachnoid space were also noted. CONCLUSION: Steady-state sequences are feasible for indirect 17O imaging with reasonable temporal resolution; this result is potentially important for the analysis of water kinetics and aquaporin function for several disorders.
  • Hiroyuki Kameda, Kohsuke Kudo, Tsuyoshi Matsuda, Taisuke Harada, Yuji Iwadate, Ikuko Uwano, Fumio Yamashita, Kunihiro Yoshioka, Makoto Sasaki, Hiroki Shirato
    Journal of magnetic resonance imaging : JMRI 48 (1) 94 - 101 1053-1807 2018/07 [Refereed][Not invited]
     
    BACKGROUND: Respiration-induced phase shift affects B0 /B1+ mapping repeatability in parallel transmission (pTx) calibration for 7T brain MRI, but is improved by breath-holding (BH). However, BH cannot be applied during long scans. PURPOSE: To examine whether interleaved acquisition during calibration scanning could improve pTx repeatability and image homogeneity. STUDY TYPE: Prospective. SUBJECTS: Nine healthy subjects. FIELD STRENGTH/SEQUENCE: 7T MRI with a two-channel RF transmission system was used. ASSESSMENT: Calibration scanning for B0 /B1+ mapping was performed under sequential acquisition/free-breathing (Seq-FB), Seq-BH, and interleaved acquisition/FB (Int-FB) conditions. The B0 map was calculated with two echo times, and the B1+ map was obtained using the Bloch-Siegert method. Actual flip-angle imaging (AFI) and gradient echo (GRE) imaging were performed using pTx and quadrature-Tx (qTx). All scans were acquired in five sessions. Repeatability was evaluated using intersession standard deviation (SD) or coefficient of variance (CV), and in-plane homogeneity was evaluated using in-plane CV. STATISTICAL TESTS: A paired t-test with Bonferroni correction for multiple comparisons was used. RESULTS: The intersession CV/SDs for the B0 /B1+ maps were significantly smaller in Int-FB than in Seq-FB (Bonferroni-corrected P < 0.05 for all). The intersession CVs for the AFI and GRE images were also significantly smaller in Int-FB, Seq-BH, and qTx than in Seq-FB (Bonferroni-corrected P < 0.05 for all). The in-plane CVs for the AFI and GRE images in Seq-FB, Int-FB, and Seq-BH were significantly smaller than in qTx (Bonferroni-corrected P < 0.01 for all). DATA CONCLUSION: Using interleaved acquisition during calibration scans of pTx for 7T brain MRI improved the repeatability of B0 /B1+ mapping, AFI, and GRE images, without BH. LEVEL OF EVIDENCE: 1 Technical Efficacy Stage 1 J. Magn. Reson. Imaging 2017.
  • Ryo Morita, Daisuke Abo, Takeshi Soyama, Yusuke Sakuhara, Masayoshi Kajiyama, Kohsuke Kudo
    Interventional Radiology 3 (2) 88 - 92 2018/06/30 [Refereed]
     
    A 50-year-old woman with liver dysfunction complained of back pain. Computed tomography showed multiple fusiform aneurysms in the right and left hepatic arteries. As she was hemodynamically stable, antihypertensive therapy was selected to reduce the risk of rupture. During hospitalization, spontaneous and progressive thrombosis formation of multiple hepatic artery aneurysms was observed. She was diagnosed with segmental arterial mediolysis based on her clinical course and imaging findings, and she was discharged after 48 days. One year following discharge, computed tomography showed complete recovery and patent, normal hepatic arterial branches. Segmental arterial mediolysis should be considered as a condition that can cause multiple hepatic artery aneurysms, which can be treated successfully with antihypertensive therapy and careful follow-up observation with imaging when the patient's hemodynamic state is stable.
  • 経皮経瘻孔的ドレナージを施行しえた術後膿瘍の5例
    曽山 武士, 阿保 大介, 加藤 大貴, 吉野 裕紀, 森田 亮, 工藤 與亮
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 33 (1) 55 - 55 1340-4520 2018/05
  • 用手的に彎曲させた18G PTCD針を用いた膿瘍ドレナージの経験
    曽山 武士, 阿保 大介, 吉野 裕紀, 森田 亮, 加藤 大貴, 工藤 與亮
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 33 (1) 55 - 56 1340-4520 2018/05
  • 肝原発類上皮血管内皮腫に対してTACE/RFAを施行した1例
    森田 亮, 山口 晃典, 阿保 大介, 曽山 武士, 加藤 大貴, 吉野 裕紀, 工藤 與亮, 宮本 憲幸, 深谷 進司, 梶山 政義
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 33 (1) 58 - 58 1340-4520 2018/05
  • 先端J型6F guiding sheath(Parent plus60)を用いたTAEの初期経験
    阿保 大介, 曽山 武士, 森田 亮, 加藤 大貴, 吉野 裕紀, 工藤 與亮
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 33 (1) 58 - 58 1340-4520 2018/05
  • 0.017inch電気離脱式マイクロコイル(Target XXL360 Detachable Coils)を用いたTAEの初期経験
    阿保 大介, 曽山 武士, 森田 亮, 加藤 大貴, 吉野 裕紀, 工藤 與亮
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 33 (1) 58 - 58 1340-4520 2018/05
  • Coaxial biopsy needle(Missionコアニードル)の初期使用経験
    加藤 大貴, 阿保 大介, 曽山 武士, 森田 亮, 吉野 裕紀, 工藤 與亮
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 33 (1) 58 - 58 1340-4520 2018/05
  • Double wire techniqueとステアリングマイクロカテーテルを用いて治療しえた肺AVFの1例
    加藤 大祐, 阿保 大介, 曽山 武士, 森田 亮, 吉野 裕紀, 加藤 大貴, 工藤 與亮
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 33 (1) 58 - 58 1340-4520 2018/05
  • Daichi Nakagawa, Kohsuke Kudo, Olatilewa Awe, Mario Zanaty, Yasunori Nagahama, Cameron Cushing, Vincent Magnotta, Minako Hayakawa, Lauren Allan, Jeremy Greenlee, Issam A Awad, Timothy Carroll, James Torner, Madhavan L Raghavan, David M Hasan
    Journal of neurosurgery 130 (4) 1 - 7 0022-3085 2018/05/01 [Refereed][Not invited]
     
    OBJECTSentinel headaches (SHs) associated with cerebral aneurysms (CAs) could be due to microbleeds, which are considered a sign that an aneurysm is unstable. Despite the prognostic importance of these microbleeds, they remain difficult to detect using routine imaging studies. The objective of this pilot study is to detect microbleeds associated with SH using a magnetic resonance imaging (MRI) quantitative susceptibility mapping (QSM) sequence and then evaluate the morphological characteristics of unstable aneurysms with microbleeds.METHODSTwenty CAs in 16 consecutive patients with an initial presentation of headache (HA) leading to a diagnosis of CA were analyzed. Headaches in 4 of the patients (two of whom had 2 aneurysms each) met the typical definition of SH, and the other 12 patients (two of whom also had 2 aneurysms each) all had migraine HA. All patients underwent imaging with the MRI-QSM sequence. Two independent MRI experts who were blinded to the patients' clinical history performed 3D graphical analysis to evaluate for potential microbleeds associated with these CAs. Computational flow and morphometric analyses were also performed to estimate wall shear and morphological variables.RESULTSIn the 4 patients with SH, MRI-QSM results were positive for 4 aneurysms, and hence these aneurysms were considered positive for non-heme ferric iron (microbleeds). The other 16 aneurysms were negative. Among aneurysm shape indices, the undulation index was significantly higher in the QSM-positive group than in the QSM-negative group. In addition, the spatial averaged wall shear magnitude was lower in the aneurysm wall in direct contact with microbleeds.CONCLUSIONSMRI-QSM allows for objective detection of microbleeds associated with SH and therefore identification of unstable CAs. CAs with slightly greater undulation indices are associated with positive MRI-QSM results and hence with microbleeds. Studies with larger populations are needed to confirm these preliminary findings.
  • Kohsuke Kudo, Taisuke Harada, Hiroyuki Kameda, Ikuko Uwano, Fumio Yamashita, Satomi Higuchi, Kunihiro Yoshioka, Makoto Sasaki
    Journal of magnetic resonance imaging : JMRI 47 (5) 1373 - 1379 1053-1807 2018/05 [Refereed][Not invited]
     
    BACKGROUND: Few studies have been reported for T2 -weighted indirect 17 O imaging. PURPOSE/HYPOTHESIS: To evaluate the feasibility of steady-state sequences for indirect 17 O brain imaging. STUDY TYPE: Signal simulation, phantom measurements, and prospective animal experiments were performed in accordance with the institutional guidelines for animal experiments. POPULATION/SUBJECTS/PHANTOM/SPECIMEN/ANIMAL MODEL: Signal simulations of balanced steady-state free precession (bSSFP) were performed for concentrations of 17 O ranging from 0.037-1.600%. Phantom measurements with concentrations of 17 O water ranging from 0.037-1.566% were also conducted. Six healthy beagle dogs were scanned with intravenous administration of 20% 17 O-labeled water (1 mL/kg). FIELD STRENGTH/SEQUENCE: Dynamic 3D-bSSFP scans were performed at 3T MRI. 17 O-labeled water was injected 60 seconds after the scan start, and the total scan duration was 5 minutes. ASSESSMENT: Based on the result of signal simulation and phantom measurement, signal changes in the beagle dogs were measured and converted into 17 O concentrations. STATISTICAL TESTS: The 17 O concentrations were averaged for every 15 seconds, and compared to the baseline (30-45 sec) with Dunnett's multiple comparison tests. RESULTS: Signal simulation revealed that the relationships between 17 O concentration and the natural logarithm of relative signals were linear. The intraclass correlation coefficient between relative signals in phantom measurement and signal simulations was 0.974. In the animal experiments, significant increases in 17 O concentration (P < 0.05) were observed 60 seconds after the injection of 17 O. At the end of scanning, mean respective 17 O concentrations of 0.084 ± 0.026%, 0.117 ± 0.038, 0.082 ± 0.037%, and 0.049 ± 0.004% were noted for the cerebral cortex, cerebellar cortex, cerebral white matter, and ventricle. DATA CONCLUSION: Dynamic steady-state sequences were feasible for indirect 17 O imaging, and absolute quantification was possible. This method can be applied for the measurement of permeability and blood flow in the brain, and for kinetic analysis of cerebrospinal fluid. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2018;47:1373-1379.
  • 縦隔に発生したpsammomatous melanotic schwannomaの一切除例
    小田 義崇, 桑原 健, 中 智昭, 樋田 泰浩, 加賀 基知三, 藪崎 哲史, 工藤 與亮, 三橋 智子, 田中 伸哉, 松野 吉宏
    日本病理学会会誌 (一社)日本病理学会 107 (1) 469 - 469 0300-9181 2018/04 [Refereed][Not invited]
  • Kiyohiro Houkin, Hideo Shichinohe, Koji Abe, Teruyo Arato, Mari Dezawa, Osamu Honmou, Nobutaka Horie, Yasuo Katayama, Kohsuke Kudo, Satoshi Kuroda, Tomohiro Matsuyama, Ichiro Miyai, Izumi Nagata, Kuniyasu Niizuma, Ken Sakushima, Masanori Sasaki, Norihiro Sato, Kenji Sawanobori, Satoshi Suda, Akihiko Taguchi, Teiji Tominaga, Haruko Yamamoto, Toru Yamashita, Toshiki Yoshimine
    Stroke 49 (4) e145-e152 - + 0039-2499 2018/04 [Refereed][Not invited]
  • 長期間経過を追えたCerebral Amyloid Angiopathyの1例
    常田 慧徳, 原田 太以佑, 吉田 篤司, 清水 幸衣, 藤間 憲幸, 工藤 與亮, 西村 洋昭, 佐々木 秀直, Khin Khin Tha, 白土 博樹
    Japanese Journal of Radiology (公社)日本医学放射線学会 36 (Suppl.) 13 - 13 1867-1071 2018/02
  • 亜急性連合性脊髄変性症の1例
    長島 諒太, 原田 太以佑, 吉田 篤司, 清水 幸衣, 藤間 憲幸, 工藤 與亮, Khin Khin Tha, 白土 博樹, 西村 洋昭, 佐々木 秀直
    Japanese Journal of Radiology (公社)日本医学放射線学会 36 (Suppl.) 16 - 16 1867-1071 2018/02
  • ステアリングマイクロカテーテルの初期使用経験
    曽山 武士, 阿保 大介, 森田 亮, 作原 祐介, 工藤 與亮, 吉田 大介
    Japanese Journal of Radiology (公社)日本医学放射線学会 36 (Suppl.) 1 - 1 1867-1071 2018/02
  • Keita Sakamoto, Noriko Oyama-Manabe, Osamu Manabe, Tadao Aikawa, Yasuka Kikuchi, Harue Sasai-Masuko, Masanao Naya, Kohsuke Kudo, Fumi Kato, Nagara Tamaki, Hiroki Shirato
    Japanese journal of radiology 36 (2) 103 - 112 1867-1071 2018/02 [Refereed][Not invited]
     
    PURPOSE: To evaluate heterogeneity of myocardial contraction in relation to extensive late gadolinium enhancement (LGE) in hypertrophic cardiomyopathy (HCM) patients with preserved left ventricular ejection fraction, using fast strain-encoded magnetic resonance imaging. MATERIALS AND METHODS: Twenty-two HCM patients and 24 age-matched control subjects were included in this retrospective study. The regional and global peak values of longitudinal and circumferential strain (LSregional, LSglobal, CSregional, CSglobal), and their regional heterogeneities were evaluated using coefficients of variation (LSCoV, CSCoV) in relation to LGE. Receiver operating characteristic curve analysis was performed to identify patients with a total left ventricular myocardial LGE ≥ 15%. RESULTS: LSglobal in HCM patients was significantly decreased compared to that in controls (- 14.4 ± 2.4% vs - 17.2 ± 2.0%; p = 0.0004), while CSglobal was not (p = 1.0). Negative LGE segments demonstrated decreased LSregional in HCM patients compared to in controls (p < 0.0001), while CSregional was not decreased. CSCoV demonstrated the largest area under the curve (AUC) (0.91), with high sensitivity (83%) and specificity (94%) for detection of HCM patients with extensive LGE, while the AUC of LSCoV was low (0.49). CONCLUSION: The heterogeneity in CSregional has a high diagnostic value for detection of HCM patients with extensive LGE.
  • Noriyuki Fujima, Tomohiro Sakashita, Akihiro Homma, Daisuke Yoshida, Kohsuke Kudo, Hiroki Shirato
    Magnetic resonance in medical sciences : MRMS : an official journal of Japan Society of Magnetic Resonance in Medicine 17 (1) 21 - 27 1347-3182 2018/01/10 [Refereed][Not invited]
     
    PURPOSE: To evaluate the diagnostic power of hybrid intravoxel incoherent motion (IVIM)-diffusion kurtosis imaging (DKI) model parameters in pretreatment for the prediction of future distant metastasis in head and neck squamous cell carcinoma (HNSCC) patients. MATERIALS AND METHODS: We retrospectively evaluated 49 HNSCC patients who underwent curative chemoradiation therapy. Diffusion-weighted image (DWI) acquired by single-shot spin-echo echo-planar imaging with 12 b-values (0-2000) was performed in all patients before any treatment. We calculated the IVIM-DKI parameters and the conventional apparent diffusion coefficient (ADC) in the ROI placed on the primary lesion. The presence of future distant metastasis was determined by histological findings or clinical follow-up. RESULTS: A univariate analysis revealed significant differences between the patients with distant metastasis and those without in slow diffusion coefficient (D) and kurtosis value (K). Highest diagnostic accuracy was obtained by the D value. In addition, a multivariate analysis revealed that the D value was an independent predictor of future distant metastasis. CONCLUSION: The D and K values obtained by this hybrid IVIM-DKI model can be one of the diagnostic tools for the prediction of future distant metastasis in HNSCC patients.
  • 先天性門脈体循環シャントによる門脈肺高血圧症疑いに対しAMPLATZER Vascular Plug IIで塞栓術を施行した1例
    曽山 武士, 阿保 大介, 森田 亮, 作原 祐介, 工藤 與亮, 辻野 一三, 中谷 資隆
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 32 (4) 324 - 325 1340-4520 2018/01
  • 肝硬変・脾腫に伴う未破裂脾動脈瘤に対するTAE症例の検討
    阿保 大介, 作原 祐介, 曽山 武士, 森田 亮, 工藤 與亮
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 32 (4) 325 - 325 1340-4520 2018/01
  • 肝切除前門脈塞栓術による残肝容積増大に関連する予測因子の検討
    作原 祐介, 阿保 大介, 曽山 武士, 森田 亮, 工藤 與亮
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 32 (4) 325 - 325 1340-4520 2018/01
  • 標的血管へのカニュレーションに難渋した左胸腔内出血の1例
    曽山 武士, 阿保 大介, 森田 亮, 作原 祐介, 工藤 與亮, 阿部 早和子, 高松 航, 藤枝 雄一郎
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 32 (4) 325 - 325 1340-4520 2018/01
  • 肝腫瘍術後の肝部下大静脈狭窄に対してステント留置を施行した1例
    亀田 浩之, 阿保 大介, 曽山 武士, 森田 亮, 作原 祐介, 工藤 與亮, 若山 顕治, 蒲池 浩文, 神山 俊哉
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 32 (4) 326 - 326 1340-4520 2018/01
  • 肝エキノコックス症術後の残存病変増大に伴う右肝静脈狭窄に対しステント留置を施行した1例
    木野田 直也, 作原 祐介, 森田 亮, 曽山 武士, 阿保 大介, 工藤 與亮, 若山 顕治, 折茂 達也, 神山 俊哉
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 32 (4) 326 - 327 1340-4520 2018/01
  • Kinya Ishizaka, Kohsuke Kudo, Kuniaki Harada, Toru Shirai, Taro Fujiwara, Suzuko Aoike, Sayaka Takamori, Hiroki Shirato
    Journal of magnetic resonance imaging : JMRI 47 (1) 123 - 130 1053-1807 2018/01 [Refereed][Not invited]
     
    PURPOSE: To evaluate the homogeneity of the radiofrequency magnetic field (B1+ ) and signal intensity using different arm positions during 3T thoracolumbar spinal imaging. MATERIALS AND METHODS: Twenty volunteers were scanned with a four-channel radiofrequency (RF) transmit coil at 3T, with arms on the bed (conventional), arms elevated by 100 mm (arm lift), or with the arms-up position (elevated arm). Axial B1+ maps and sagittal T1 -weighted image (T1 WI)-performed RF shimming were obtained for each arm position. The mean and standard deviation (SD) of the flip angle (FA) at the center of the vertebra on each B1+ map, and contrast noise ratios (CNRs) between the spinal cord and cerebrospinal fluid of sagittal T1 WI, were calculated and compared among the different arm positions. RESULTS: Mean FA values (degrees) for the arm lift and elevated arm positions were significantly larger than for the conventional position (P < 0.001 for both) at the twelfth thoracic vertebra (Th12). FA SD values for the arm lift and elevated arm position were significantly smaller than for the conventional position (P < 0.001 for both) at Th12. CNR for the arm lift and elevated arm position were significantly higher than for the conventional position (P = 0.007 and 0.002, respectively). The mean and SD of the FA and the CNR did not differ significantly for the arm lift and elevated arm positions (P = 0.591, 0.958, and 0.927, respectively). CONCLUSION: Inhomogeneities of B1+ and signal intensities were improved by simply changing the arm position in 3T thoracolumbar spinal imaging. LEVEL OF EVIDENCE: 3 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2018;47:123-130.
  • Khin Khin Tha, Ulrich Katscher, Shigeru Yamaguchi, Christian Stehning, Shunsuke Terasaka, Noriyuki Fujima, Kohsuke Kudo, Ken Kazumata, Toru Yamamoto, Marc Van Cauteren, Hiroki Shirato
    European radiology 28 (1) 348 - 355 0938-7994 2018/01 [Refereed][Not invited]
     
    OBJECTIVES: This study noninvasively examined the electrical conductivity (σ) characteristics of diffuse gliomas using MRI and tested its validity. METHODS: MRI including a 3D steady-state free precession (3D SSFP) sequence was performed on 30 glioma patients. The σ maps were reconstructed from the phase images of the 3D SSFP sequence. The σ histogram metrics were extracted and compared among the contrast-enhanced (CET) and noncontrast-enhanced tumour components (NCET) and normal brain parenchyma (NP). Difference in tumour σ histogram metrics among tumour grades and correlation of σ metrics with tumour grades were tested. Validity of σ measurement using this technique was tested by correlating the mean tumour σ values measured using MRI with those measured ex vivo using a dielectric probe. RESULTS: Several σ histogram metrics of CET and NCET of diffuse gliomas were significantly higher than NP (Bonferroni-corrected p ≤ .045). The maximum σ of NCET showed a moderate positive correlation with tumour grade (r = .571, Bonferroni-corrected p = .018). The mean tumour σ measured using MRI showed a moderate positive correlation with the σ measured ex vivo (r = .518, p = .040). CONCLUSIONS: Tissue σ can be evaluated using MRI, incorporation of which may better characterise diffuse gliomas. KEY POINTS: • This study tested the validity of noninvasive electrical conductivity measurements by MRI. • This study also evaluated the electrical conductivity characteristics of diffuse glioma. • Gliomas have higher electrical conductivity values than the normal brain parenchyma. • Noninvasive electrical conductivity measurement can be helpful for better characterisation of glioma.
  • Psammomatous melanotic schwannomaの1切除例
    小田 義崇, 桑原 健, 中 智昭, 三橋 智子, 松野 吉宏, 樋田 泰浩, 加賀 基知三, 藪崎 哲史, 工藤 與亮
    肺癌 (NPO)日本肺癌学会 57 (7) 916 - 916 0386-9628 2017/12 [Refereed][Not invited]
  • J-I. Nomura, I. Uwano, M. Sasaki, K. Kudo, F. Yamashita, K. Ito, S. Fujiwara, M. Kobayashi, K. Ogasawara
    AMERICAN JOURNAL OF NEURORADIOLOGY 38 (12) 2327 - 2333 0195-6108 2017/12 [Refereed][Not invited]
     
    BACKGROUND AND PURPOSE: Preoperative hemodynamic impairment in the affected cerebral hemisphere is associated with the development of cerebral hyperperfusion following carotid endarterectomy. Cerebral oxygen extraction fraction images generated from 7T MR quantitative susceptibility mapping correlate with oxygen extraction fraction images on positron-emission tomography. The present study aimed to determine whether preoperative oxygen extraction fraction imaging generated from 7T MR quantitative susceptibility mapping could identify patients at risk for cerebral hyperperfusion following carotid endarterectomy. MATERIALS AND METHODS: Seventy-seven patients with unilateral internal carotid artery stenosis (70%) underwent preoperative 3D T2*-weighted imaging using a multiple dipole-inversion algorithm with a 7T MR imager. Quantitative susceptibility mapping images were then obtained, and oxygen extraction fraction maps were generated. Quantitative brain perfusion single-photon emission CT was also performed before and immediately after carotid endarterectomy. ROIs were automatically placed in the bilateral middle cerebral artery territories in all images using a 3D stereotactic ROI template, and affected-to-contralateral ratios in the ROIs were calculated on quantitative susceptibility mapping-oxygen extraction fraction images. RESULTS: Ten patients (13%) showed post-carotid endarterectomy hyperperfusion (cerebral blood flow increases of 100% compared with preoperative values in the ROIs on brain perfusion SPECT). Multivariate analysis showed that a high quantitative susceptibility mapping-oxygen extraction fraction ratio was significantly associated with the development of post-carotid endarterectomy hyperperfusion (95% confidence interval, 33.5-249.7; P = .002). Sensitivity, specificity, and positive- and negative-predictive values of the quantitative susceptibility mapping-oxygen extraction fraction ratio for the prediction of the development of post-carotid endarterectomy hyperperfusion were 90%, 84%, 45%, and 98%, respectively. CONCLUSIONS: Preoperative oxygen extraction fraction imaging generated from 7T MR quantitative susceptibility mapping identifies patients at risk for cerebral hyperperfusion following carotid endarterectomy.
  • Satoshi Yabusaki, Noriko Oyama-Manabe, Osamu Manabe, Kenji Hirata, Fumi Kato, Noriyuki Miyamoto, Yoshihiro Matsuno, Kohsuke Kudo, Nagara Tamaki, Hiroki Shirato
    EJNMMI research 7 (1) 20 - 20 2191-219X 2017/12 [Refereed][Not invited]
     
    BACKGROUND: We aimed to assess the positivity, distribution, quantitative degree of vessel inflammation, and clinical characteristics of IgG4-related aortitis/periarteritis and periarteritis (IgG4-aortitis), and to examine the difference in these characteristics between cases with and without IgG4-aortitis, using fluorodeoxyglucose positron-emission tomography/computed tomography (FDG-PET/CT) co-registered with contrast-enhanced CT (CECT). We retrospectively evaluated 37 patients with IgG4-related disease (IgG4-RD) who underwent both FDG-PET/CT and CECT. The arterial SUVmax and its value normalized to the background venous blood pool (BP)-the target-to-background ratio (TBR) in the entire aorta and the major first branches-were measured. Active vascular inflammation was considered in cases with a higher FDG uptake than BP and a thickened arterial wall (>2 mm). RESULTS: Fifteen (41%) patients exhibited IgG4-aortitis. Most patients (80%) showed multiple region involvement. The entire aorta, including the major first branches, were involved, typically showing a thickened wall and high FDG uptakes. The most common site was the iliac arteries (35%), followed by the infrarenal abdominal aorta (33%), thoracic aorta (8%), first branches of the thoracic aorta (8%), suprarenal abdominal aorta (6%), and the first branches of the abdominal aorta (5%). The IgG4-aortitis-positive vessel regions were thickened, with an average maximal wall thickness of 6.3 ± 2.9 mm. The SUVmax and TBR values were significantly higher in the IgG4-aortitis-positive regions (median 3.7 [1.6-5.5] and 2.1 [1.4-3.7], respectively) than in the IgG4-aortitis-negative regions (median 2.1 [1.2-3.7] and 1.3 [0.9-2.3], respectively; p < 0.0001). The IgG4-aortitis-positive group patients were older (69.5 ± 6.0 vs. 63.3 ± 12.6 years, respectively) and had a higher male predominance (80 vs. 55%, respectively) than the negative group, although the differences were not significant (p = 0.17 and p = 0.06, respectively). CONCLUSIONS: We investigated the image characteristics of IgG4-aortitis. The entire aorta and major branches can be involved with more than 2-fold higher FDG uptake than the venous background pool, and with wall thickening. The most common involved site is the iliac arteries, followed by the infrarenal abdominal aorta.
  • 術前7 Tesla定量的磁化率マップ(QSM)によるOEF画像を用いた頸動脈内膜剥離術後過灌流出現の予知
    野村 順一, 上野 育子, 佐々木 真理, 工藤 與亮, 山下 典生, 伊藤 賢司, 松本 昌泰, 及川 公樹, 藤原 俊朗, 千田 光平, 寺崎 一典, 小林 正和, 吉田 研二, 小笠原 邦昭
    脳循環代謝 日本脳循環代謝学会 29 (1) 169 - 169 0915-9401 2017/11 [Not refereed][Not invited]
  • Hiroyuki Sugimori, Noriyuki Fujima, Yuriko Suzuki, Hiroyuki Hamaguchi, Kinya Ishizaka, Kohsuke Kudo
    Magnetic resonance imaging 43 136 - 143 0730-725X 2017/11 [Refereed][Not invited]
     
    PURPOSE: To establish an optimized sequence design for fast acceleration of arterial spin labeling (ASL)-based time-resolved magnetic resonance angiography (MRA) by acquisition of control and labeled images in the same shot (fast ACTRESS) and a scan time of <1min, for the evaluation of intracranial vessels. MATERIALS AND METHODS: Ten healthy volunteers with no unilateral symptomatic arterial stenosis, who underwent 3-tesla MRI, were investigated. Imaging parameters for the fast ACTRESS sequence were set with an acquisition time of 45s. During post-processing, the first phase in the multi-phase readout, which was defined as the control image, was subtracted from each of the other phases. Thus, four-dimensional (4D)-MRA images of each phase were obtained. The maximum intensity projection was used for the reconstruction of 4D-MRA images and time-to-signal intensity curves (TIC) obtained for each vessel. The area under the curve (AUC), peak time, and maximum signal intensity were obtained from TIC. The different labeling types were broadly divided into six groups: L1, L2, L3, L4, L5, and L6 according to the actual number of labeling pulse. RESULTS: A total of 5040 regions of interest were evaluated. The peak SI of L3, except for those in the A2 segment of the anterior cerebral artery, was significantly higher than that of L5. However, there were no significant differences between L4 and L5. Although the AUCs of L3 and L4 for anterior circulation were relatively higher than that of the other subgroups, the AUC of L3 was significantly higher than that of L4. CONCLUSION: The fast ACTRESS was optimized and indicated that the labeling type of L3 was the most appropriate for the well visualization of intracranial arteries. The fast ACTRESS sequence was useful to acquire well-delineated images of intracranial vessels in ˂1min.
  • 原田 太以佑, 藤間 憲幸, 工藤 與亮
    臨床画像 (株)メジカルビュー社 33 (10) 1116 - 1129 0911-1069 2017/10 
    薬物治療に関連する中枢神経病変は非常に多彩であるが,画像診断医が薬剤性病変の可能性を言及することが肝要である。本稿では最近よく話題となっている分子標的薬に焦点をあてつつ,日常臨床でしばしば見かける薬剤関連病変の画像所見を概説する。(著者抄録)
  • Tadao Aikawa, Noriko Oyama-Manabe, Masanao Naya, Hiroshi Ohira, Ayako Sugimoto, Ichizo Tsujino, Masahiko Obara, Osamu Manabe, Kohsuke Kudo, Hiroyuki Tsutsui, Nagara Tamaki
    European radiology 27 (10) 4054 - 4063 0938-7994 2017/10 [Refereed][Not invited]
     
    OBJECTIVES: To evaluate the diagnostic value of delayed contrast-enhanced computed tomography (DE-CT) for cardiac sarcoidosis (CS) in patients with or without implantable devices, including a quantitative comparison with late gadolinium enhancement cardiac magnetic resonance (LGE-CMR). METHODS: Twenty-four patients (mean age, 64 ± 9 years; 17 women) with known or suspected CS underwent retrospective electrocardiogram-gated DE-CT at 80 kV with knowledge-based iterative model reconstruction. Fourteen patients without implantable devices also underwent LGE-CMR, while ten with pacemakers or implantable cardioverter-defibrillators did not. The presence of hyperenhanced myocardium was assessed visually and quantitatively using a 5-standard deviation threshold above the mean of remote myocardium. RESULTS: Inter-observer agreement for visual detection of hyperenhanced segments on DE-CT was excellent in patients with implantable devices and in those without (κ = 0.91 and κ = 0.94, respectively). Comparisons of the percent area of hyperenhanced myocardium between DE-CT and LGE-CMR on both per-patient and per-segment analyses showed good correlations (r = 0.96 and r = 0.83, respectively; p < 0.001). The sensitivity and specificity of DE-CT for the diagnosis of CS were 94% and 33%. CONCLUSIONS: The extent of hyperenhanced lesion with DE-CT showed good agreement with LGE-CMR results. DE-CT showed high sensitivity for detecting CS and may be useful particularly in patients with contraindications to CMR. KEY POINTS: • Delayed contrast-enhanced CT (DE-CT) can be applied to patients with implantable devices. • DE-CT can detect cardiac sarcoidosis (CS) lesions similarly to cardiac MRI. • DE-CT shows high sensitivity for detecting CS. • DE-CT may be useful particularly in patients with contraindications to cardiac MRI.
  • 救命率を向上させる外科とIVRとのコラボレーション 救命率を向上させる外科とIVRとのコラボレーション症例
    森田 亮, 曽山 武士, 阿保 大介, 工藤 與亮
    Japanese Journal of Acute Care Surgery 日本Acute Care Surgery学会 7 (1) 117 - 117 2017/09
  • 超音波ガイド下に経皮経瘻孔的にドレナージ施行できた術後膿瘍の5例
    曽山 武士, 阿保 大介, 加藤 大貴, 吉野 裕紀, 森田 亮, 工藤 與亮
    日本医学放射線学会秋季臨床大会抄録集 (公社)日本医学放射線学会 53回 S493 - S493 0048-0428 2017/08
  • 鎖骨下静脈の虚脱改善における手技的工夫の比較検討
    加藤 大祐, 森田 亮, 曽山 武士, 阿保 大介, 高橋 文也, 宮本 憲幸, 工藤 與亮
    日本医学放射線学会秋季臨床大会抄録集 (公社)日本医学放射線学会 53回 S497 - S497 0048-0428 2017/08
  • Ikuko Uwano, Kohsuke Kudo, Ryota Sato, Kuniaki Ogasawara, Hiroyuki Kameda, Jun-Ichi Nomura, Futoshi Mori, Fumio Yamashita, Kenji Ito, Kunihiro Yoshioka, Makoto Sasaki
    Stroke 48 (8) 2136 - 2141 0039-2499 2017/08 [Refereed][Not invited]
     
    BACKGROUND AND PURPOSE: The oxygen extraction fraction (OEF) is an effective metric to evaluate metabolic reserve in chronic ischemia. However, OEF is considered to be accurately measured only when using positron emission tomography (PET). Thus, we investigated whether OEF maps generated by magnetic resonance quantitative susceptibility mapping (QSM) at 7 Tesla enabled detection of OEF changes when compared with those obtained with PET. METHODS: Forty-one patients with chronic stenosis/occlusion of the unilateral internal carotid artery or middle cerebral artery were examined using 7 Tesla-MRI and PET scanners. QSM images were obtained from 3-dimensional T2*-weighted images, using a multiple dipole-inversion algorithm. OEF maps were generated based on susceptibility differences between venous structures and brain tissues on QSM images. OEF ratios of the ipsilateral middle cerebral artery territory against the contralateral side were calculated on the QSM-OEF and PET-OEF images, using an anatomic template. RESULTS: The OEF ratio in the middle cerebral artery territory showed significant correlations between QSM-OEF and PET-OEF maps (r=0.69; P<0.001), especially in patients with a substantial increase in the PET-OEF ratio of 1.09 (r=0.79; P=0.004), although showing significant systematic biases for the agreements. An increased QSM-OEF ratio of >1.09, as determined by receiver operating characteristic analysis, showed a sensitivity and specificity of 0.82 and 0.86, respectively, for the substantial increase in the PET-OEF ratio. Absolute QSM-OEF values were significantly correlated with PET-OEF values in the patients with increased PET-OEF. CONCLUSIONS: OEF ratios on QSM-OEF images at 7 Tesla showed a good correlation with those on PET-OEF images in patients with unilateral steno-occlusive internal carotid artery/middle cerebral artery lesions, suggesting that noninvasive OEF measurement by MRI can be a substitute for PET.
  • 卵巣癌根治術後難治性リンパ漏に対しリンパ管造影にて治癒したと思われる1例
    木野田 直也, 森田 亮, 曽山 武士, 阿保 大介, 作原 祐介, 工藤 與亮, 嶋田 知紗, 金野 陽輔
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 32 (2) 160 - 160 1340-4520 2017/07
  • 多発性嚢胞腎に対するエンボスフィアによる腎動脈塞栓術の初期経験
    作原 祐介, 森田 亮, 曽山 武士, 阿保 大介, 加藤 大貴, 工藤 與亮, 西尾 妙織
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 32 (2) 160 - 160 1340-4520 2017/07
  • IVR術中のオンサイトでの画像参照環境整備の試み
    阿保 大介, 曽山 武士, 作原 祐介, 森田 亮, 吉川 仁人, 工藤 與亮
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 32 (2) 162 - 162 1340-4520 2017/07
  • Takeshi Soyama, Daisuke Yoshida, Yusuke Sakuhara, Ryo Morita, Daisuke Abo, Kohsuke Kudo
    Cardiovascular and interventional radiology 40 (6) 947 - 952 0174-1551 2017/06 [Refereed][Not invited]
     
    The steerable microcatheter (SwiftNINJA, Sumitomo Bakelite, Tokyo, Japan), which has a remote-controlled flexible tip manipulated using a dial in the handgrip, was recently developed and delivered to the market. This device enables the user to change the angle of the microcatheter tip manually, and potentially makes selective catheterisation easier. We evaluated its unique characteristics and utility in selective catheterisation and coil embolization. This article describes: (1) the advantages of this device in catheterisations involving acute angle branches, and (2) a new technique of compact coil packing with the use of intentional folding by the bendable tip of the catheter.
  • Noriyuki Fujima, Tomohiro Sakashita, Akihiro Homma, Taisuke Harada, Yukie Shimizu, Khin Khin Tha, Kohsuke Kudo, Hiroki Shirato
    Oncotarget 8 (20) 33631 - 33643 1949-2553 2017/05/16 [Refereed][Not invited]
     
    We assessed parameters of advanced diffusion weighted imaging (DWI) models for the prediction of the tumor growth rate in 55 head and neck squamous cell carcinoma (HNSCC) patients. The DWI acquisition used single-shot spin-echo echo-planar imaging with 12 b-values (0-2000). We calculated 14 DWI parameters using mono-exponential, bi-exponential, tri-exponential, stretched exponential and diffusion kurtosis imaging models. We directly measured the tumor growth rate from two sets of different-date imaging data. We divided the patients into a discovery group (n = 40) and validation group (n = 15) based on their MR acquisition dates. In the discovery group, we performed univariate and multivariate regression analyses to establish the multiple regression equation for the prediction of the tumor growth rate using diffusion parameters. The equation obtained with the discovery group was applied to the validation group for the confirmation of the equation's accuracy. After the univariate and multivariate regression analyses in the discovery-group patients, the estimated tumor growth rate equation was established by using the significant parameters of intermediate diffusion coefficient D2 and slow diffusion coefficient D3 obtained by the tri-exponential model. The discovery group's correlation coefficient between the estimated and directly measured tumor growth rates was 0.74. In the validation group, the correlation coefficient (r = 0.66) and intra-class correlation coefficient (0.65) between the estimated and directly measured tumor growth rates were respectively good. In conclusion, advanced DWI model parameters can be a predictor for determining HNSCC patients' tumor growth rate.
  • Noriyuki Fujima, Daisuke Yoshida, Tomohiro Sakashita, Akihiro Homma, Kohsuke Kudo, Hiroki Shirato
    European journal of radiology 90 14 - 19 0720-048X 2017/05 [Refereed][Not invited]
     
    PURPOSE: To evaluate the detectability of the residual tumour in post-treatment granulation tissue using parameters obtained with an advanced diffusion model in patients with head and neck squamous cell carcinoma (HNSCC) treated by chemoradiation therapy. MATERIALS AND METHODS: We retrospectively evaluated 23 patients with HNSCC after the full course of chemoradiation therapy. The diffusion-weighted image (DWI) acquisition used single-shot spin-echo echo-planar imaging with 11 b-values (0-1000). We calculated 10 DWI parameters using a mono-exponential model, a bi-exponential model, a stretched exponential model (SEM), a diffusion kurtosis imaging (DKI) model and a statistical diffusion model (SDM) in the region of interest (ROI) placed on the post-treatment granulation tissue. The presence of residual tumour was determined by histological findings or clinical follow-up. RESULTS: Among the 23 patients, seven patients were revealed to have residual tumour. The univariate analysis revealed significant differences in six parameters between the patients with and without residual tumour. From the receiver operating characteristic curve analysis, the highest area under curve was detected in the center of the Gaussian distribution of diffusion coefficient (Ds) obtained by the SDM. The multivariate analysis revealed that the Ds and diffusion heterogeneity (α) obtained by the SEM were predictors for the presence of residual tumour. CONCLUSION: DWI parameters obtained by advanced fitting models will be one of the diagnostic tools for the detection of residual tumour.
  • Kohsuke Kudo, Ikuko Uwano, Toshinori Hirai, Ryuji Murakami, Hideo Nakamura, Noriyuki Fujima, Fumio Yamashita, Jonathan Goodwin, Satomi Higuchi, Makoto Sasaki
    Magnetic resonance in medical sciences : MRMS : an official journal of Japan Society of Magnetic Resonance in Medicine 16 (2) 129 - 136 1347-3182 2017/04/10 [Refereed][Not invited]
     
    PURPOSE: The purpose of the present study was to compare different software algorithms for processing DSC perfusion images of cerebral tumors with respect to i) the relative CBV (rCBV) calculated, ii) the cutoff value for discriminating low- and high-grade gliomas, and iii) the diagnostic performance for differentiating these tumors. METHODS: Following approval of institutional review board, informed consent was obtained from all patients. Thirty-five patients with primary glioma (grade II, 9; grade III, 8; and grade IV, 18 patients) were included. DSC perfusion imaging was performed with 3-Tesla MRI scanner. CBV maps were generated by using 11 different algorithms of four commercially available software and one academic program. rCBV of each tumor compared to normal white matter was calculated by ROI measurements. Differences in rCBV value were compared between algorithms for each tumor grade. Receiver operator characteristics analysis was conducted for the evaluation of diagnostic performance of different algorithms for differentiating between different grades. RESULTS: Several algorithms showed significant differences in rCBV, especially for grade IV tumors. When differentiating between low- (II) and high-grade (III/IV) tumors, the area under the ROC curve (Az) was similar (range 0.85-0.87), and there were no significant differences in Az between any pair of algorithms. In contrast, the optimal cutoff values varied between algorithms (range 4.18-6.53). CONCLUSIONS: rCBV values of tumor and cutoff values for discriminating low- and high-grade gliomas differed between software packages, suggesting that optimal software-specific cutoff values should be used for diagnosis of high-grade gliomas.
  • 先天性門脈体循環シャントによる門脈肺高血圧症に対しAMPLATZER Vascular Plug2で塞栓術を施行した1例
    曽山 武士, 阿保 大介, 森田 亮, 加藤 大貴, 作原 祐介, 工藤 與亮, 辻野 一三, 中谷 資隆
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 32 (Suppl.) 231 - 231 1340-4520 2017/04
  • CT during aortographyを施行して肝外供血路を同定できた巨大肝細胞癌の2例
    加藤 大貴, 曽山 武士, 作原 祐介, 阿保 大介, 森田 亮, 工藤 與亮
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 32 (Suppl.) 352 - 352 1340-4520 2017/04
  • 腎細胞癌脛骨転移掻爬術前にTAEを施行した2例
    作原 祐介, 木村 輔, 森田 亮, 森 直樹, 曽山 武士, 阿保 大介, 工藤 與亮
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 32 (1) 81 - 81 1340-4520 2017/03
  • 子宮筋腫に対するEmbosphereを用いた子宮動脈塞栓術後に卵巣機能低下を呈した1例
    中川 純一, 木村 輔, 森田 亮, 曽山 武士, 阿保 大介, 作原 祐介, 工藤 與亮
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 32 (1) 81 - 82 1340-4520 2017/03
  • 肝性脳症に対する経皮的塞栓術の治療成績の検討
    森田 亮, 森 直樹, 木村 輔, 曽山 武士, 阿保 大介, 作原 祐介, 工藤 與亮
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 32 (1) 82 - 82 1340-4520 2017/03
  • ステアリングマイクロカテーテルの初期使用経験
    曽山 武士, 阿保 大介, 吉田 大介, 木村 輔, 森田 亮, 作原 祐介, 工藤 與亮
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 32 (1) 83 - 83 1340-4520 2017/03
  • Noriyuki Fujima, Daisuke Yoshida, Tomohiro Sakashita, Akihiro Homma, Akiko Tsukahara, Yukie Shimizu, Khin Khin Tha, Kohsuke Kudo, Hiroki Shirato
    European radiology 27 (3) 956 - 965 0938-7994 2017/03 [Refereed][Not invited]
     
    OBJECTIVES: To evaluate the diagnostic value of intravoxel incoherent motion (IVIM) and diffusional kurtosis imaging (DKI) parameters in nasal or sinonasal squamous cell carcinoma (SCC) patients to determine local control/failure. METHODS: Twenty-eight patients were evaluated. MR acquisition used single-shot spin-echo EPI with 12 b-values. Quantitative parameters (mean value, 25th, 50th and 75th percentiles) of IVIM (perfusion fraction f, pseudo-diffusion coefficient D*, and true-diffusion coefficient D), DKI (kurtosis value K, kurtosis corrected diffusion coefficient Dk) and apparent diffusion coefficient (ADC) were calculated. Parameter values at both the pretreatment and early-treatment period, and the percentage change between these two periods were obtained. RESULTS: Multivariate logistic regression analysis: the percentage changes of D (mean, 25th, 50th, 75th), K (mean, 50th, 75th), Dk (mean, 25th, 50th), and ADC (mean, 25th, 50th) were predictors of local control. ROC curve analysis: the parameter with the highest accuracy = the percentage change of D value with the histogram 25th percentile (0.93 diagnostic accuracy). Multivariate Cox regression analyses: the percentage changes of D (mean, 25th, 50th), K (mean, 50th, 75th), Dk (mean, 25th, 50th) and ADC (mean, 25th, 50th) are predictors. CONCLUSIONS: IVIM and DKI parameters, especially the D-value's histogram 25th percentile, are useful for predicting local control. KEY POINTS: • Noninvasive assessment of treatment outcome in SCC patients was achieved using IVIM/DKI. • Several IVIM and DKI parameters can predict the local control. • Especially, the D-value's histogram 25th percentile has high diagnostic accuracy.
  • Amplatzer vascular plug 4(AVP4)を用いた腹腔動脈瘤に対する塞栓術の経験
    木村 輔, 阿保 大介, 森田 亮, 曽山 武士, 作原 祐介, 工藤 與亮
    Japanese Journal of Radiology (公社)日本医学放射線学会 35 (Suppl.) 9 - 9 1867-1071 2017/02
  • Noriyuki Fujima, Tomohiro Sakashita, Akihiro Homma, Yukie Shimizu, Atsushi Yoshida, Taisuke Harada, Khin Khin Tha, Kohsuke Kudo, Hiroki Shirato
    Magnetic resonance imaging 36 16 - 23 0730-725X 2017/02 [Refereed][Not invited]
     
    PURPOSE: We assessed advanced fitting models of diffusion weighted imaging (DWI) in head/neck squamous cell carcinoma (HNSCC) patients to determine the best goodness of fit and correlations among diffusion parameters. We compared these results with those of dynamic contrast-enhanced (DCE) perfusion parameters. MATERIALS AND METHODS: We retrospectively evaluated 32 HNSCC patients (12 sinonasal, 20 pharynx/oral cavity). The DWI acquisition used single-shot spin-echo echo-planar imaging (EPI) with 12 b-values (0-2000). We calculated 14 DWI parameters using mono-exponential, bi-exponential, and tri-exponential models, stretched exponential model (SEM) and diffusion kurtosis imaging (DKI) models. We compared each model's goodness of fit using the residual sum of squares (RSS), Akaike Information Criterion (AIC) and Bayesian information criterion (BIC) value. We determined the correlation between each pair of DWI parameters and between each DWI parameter and DCE perfusion parameter. RESULTS: The tri-exponential fit's RSS, AIC and BIC values were significantly smaller than those for bi-exponential fit. The RSS, AIC and BIC values of the SEM fit and DKI fit were significantly smaller than mono-exponential model. Significant correlations were observed in 30 pairs (sinonasal cavity) and 31 (sinonasal cavity group) among 91 DWI parameter combinations. Significant correlations were also observed in nine pairs (both sinonasal cavity and pharynx/oral cavity group) among 64 DWI/DCE perfusion parameter pairs, in particular, high positive correlations between the tri-exponential model's intermediate diffusion fraction (f2) and the volume of the extracellular extravascular space per unit volume of tissue (ve) were observed in both patient groups. CONCLUSION: We identified several correlations between DWI parameters by advanced fitting models and correlations between DWI and DCE parameters. These will help determine HNSCC patients' detailed tissue structures.
  • Taisuke Harada, Kohsuke Kudo, Ikuko Uwano, Fumio Yamashita, Hiroyuki Kameda, Tsuyoshi Matsuda, Makoto Sasaki, Hiroki Shirato
    Magnetic resonance in medical sciences : MRMS : an official journal of Japan Society of Magnetic Resonance in Medicine 16 (1) 23 - 31 1347-3182 2017/01/10 [Refereed][Not invited]
     
    PURPOSE: The B0 and B1+ maps required for calculation of the radiofrequency (RF) pulse of parallel transmission (pTx) are obtained in calibration scans; however, they may be affected by respiratory motion. We aimed to compare the reproducibility of B0 and B1+ maps and gradient echo (GRE) images of the brain scanned with pTx at 7T between free-breathing (FB) and breath-holding (BH) conditions during the calibration scan. METHODS: Nine healthy volunteers were scanned by 7T MRI using a two-channel quadrature head coil. In the pTx calibration scans performed with FB and BH, the B0 map was obtained from two different TE images and the B1+ map was calculated by the Bloch-Siegert method. A GRE image (gradient-recalled-acquisition in steady state) was also obtained with RF shimming and RF design of pTx with spoke method, as well as quadrature transmission (qTx). All the scans were repeated over five sessions. The reproducibility of the B0 and B1+ maps and GRE image was evaluated with region-of-interest measurements using inter-session standard deviation (SD) and coefficient of variation (CV) values. Intensity homogeneity of GRE images was also assessed with in-plane CV. RESULTS: Inter-session SDs of B0 and B1+ maps were significantly smaller in BH (P < 0.01). Inter-session CVs of GRE images were significantly smaller in qTx than BH and FB (P < 0.01, both); however, the CVs of BH were significantly smaller (P < 0.01). In-plane CVs of FB and BH with RF shimming were not significantly different with qTx; however, CVs of FB and BH with RF design were significantly smaller than those of qTx (P < 0.05 and P < 0.01, respectively). CONCLUSION: BH could improve the reproducibility of B0 and B1+ maps in pTx calibration scans and GRE images. These results might facilitate the development of pTx in human brain at 7T.
  • Ikuko Uwano, Makoto Sasaki, Kohsuke Kudo, Timothé Boutelier, Hiroyuki Kameda, Futoshi Mori, Fumio Yamashita
    Magnetic resonance in medical sciences : MRMS : an official journal of Japan Society of Magnetic Resonance in Medicine 16 (1) 32 - 37 1347-3182 2017/01/10 [Refereed][Not invited]
     
    PURPOSE: The Bayesian estimation algorithm improves the precision of bolus tracking perfusion imaging. However, this algorithm cannot directly calculate Tmax, the time scale widely used to identify ischemic penumbra, because Tmax is a non-physiological, artificial index that reflects the tracer arrival delay (TD) and other parameters. We calculated Tmax from the TD and mean transit time (MTT) obtained by the Bayesian algorithm and determined its accuracy in comparison with Tmax obtained by singular value decomposition (SVD) algorithms. METHODS: The TD and MTT maps were generated by the Bayesian algorithm applied to digital phantoms with time-concentration curves that reflected a range of values for various perfusion metrics using a global arterial input function. Tmax was calculated from the TD and MTT using constants obtained by a linear least-squares fit to Tmax obtained from the two SVD algorithms that showed the best benchmarks in a previous study. Correlations between the Tmax values obtained by the Bayesian and SVD methods were examined. RESULTS: The Bayesian algorithm yielded accurate TD and MTT values relative to the true values of the digital phantom. Tmax calculated from the TD and MTT values with the least-squares fit constants showed excellent correlation (Pearson's correlation coefficient = 0.99) and agreement (intraclass correlation coefficient = 0.99) with Tmax obtained from SVD algorithms. CONCLUSIONS: Quantitative analyses of Tmax values calculated from Bayesian-estimation algorithm-derived TD and MTT from a digital phantom correlated and agreed well with Tmax values determined using SVD algorithms.
  • 新たな放射線治療用病変識別マーカーの開発のための基礎的検討
    作原 祐介, 阿保 大介, 曽山 武士, 森田 亮, 工藤 與亮, 白土 博樹, 高橋 文也
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 31 (4) 374 - 374 1340-4520 2017/01
  • 多発腎動脈瘤を伴う腎動静脈瘻に対し複数回のTAEを施行した1例
    森田 亮, 曽山 武士, 阿保 大介, 作原 祐介, 工藤 與亮, 佐藤 幸彦, 田口 大志, 佐澤 陽, 梶山 政義
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 31 (4) 374 - 375 1340-4520 2017/01
  • 術前TAEを施行した大腿リンパ管奇形の1例
    曽山 武士, 阿保 大介, 木村 輔, 森田 亮, 作原 祐介, 工藤 與亮, 古川 洋志, 山本 有平
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 31 (4) 375 - 375 1340-4520 2017/01
  • Amplatzer vascular plug 4(AVP4)を用いた腹腔動脈瘤に対する塞栓術の経験
    阿保 大介, 木村 輔, 曽山 武士, 作原 祐介, 森田 亮, 工藤 與亮
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 31 (4) 376 - 376 1340-4520 2017/01
  • 定量的磁化率マッピングで脳の構造と酸素代謝をみる
    工藤 與亮, 藤間 憲幸, Khin Khin Tha, 清水 幸衣, 原田 太以佑, 吉田 篤司
    臨床神経学 (一社)日本神経学会 56 (Suppl.) S62 - S62 0009-918X 2016/12
  • Noriyuki Fujima, Toshiya Osanai, Yukie Shimizu, Atsushi Yoshida, Taisuke Harada, Naoki Nakayama, Kohsuke Kudo, Kiyohiro Houkin, Hiroki Shirato
    Journal of magnetic resonance imaging : JMRI 44 (4) 834 - 45 1053-1807 2016/10 [Refereed][Not invited]
     
    PURPOSE: To evaluate the utility of a vessel-selective four-dimensional (4D) magnetic resonance angiography (MRA) technique for the evaluation of intracranial arteriovenous malformations (AVMs). MATERIALS AND METHODS: Twelve AVM patients were evaluated retrospectively. Time-of-flight (TOF) MRA, nonvessel-selective 4D-MRA (NS-4D-MRA), and vessel-selective 4D-MRA (VS-4D-MRA) were performed using a 3T MR unit in all patients, and used to identify feeding arteries and draining veins and measure nidus size. The diagnostic accuracy of the three techniques was compared using digital subtraction angiography (DSA). If a multifeeder was observed, the percentage of blood flow of each feeding artery to the entire nidus was evaluated and compared to the DSA findings using the "error value," defined as the degree of overestimation of the blood flow. All imaging findings were assessed by two neuroradiologists. RESULTS: In both raters, the detectability of feeding arteries by VS-4D-MRA (12 and 11 patients) was significantly higher than those of TOF-MRA (7 and 6 patients) and NS-4D-MRA (8 and 7 patients) (P < 0.016). The detectability of drainer veins by TOF-MRA (10 and 10 patients) was significantly higher than that of VS-4D-MRA (7 and 6 patients). In the percentage of the blood flow of each feed artery to the entire nidus, the DSA findings (error value; 27.1 ± 5.7) indicated overestimations of the blood flow compared to the VS-4D-MRA (error value; 7.1 ± 3.9) (P < 0.001). CONCLUSION: VS-4D-MRA was shown to be a useful technique for the evaluation of intracranial AVMs, especially for detecting feed arteries and estimating details of the nidus structure. J. MAGN. RESON. IMAGING 2016;44:834-845.
  • MRI計測による肺循環時間は肺高血圧重症度と相関するか
    真鍋 徳子[大山], 佐藤 隆博, 大平 洋, 辻野 一三, 中谷 資隆, 加藤 扶美, 工藤 與亮, 玉木 長良
    日独医報 バイエル薬品(株) 61 (1) 133 - 133 0912-0351 2016/09
  • 多発性嚢胞腎、多発性肝嚢胞に対する球状塞栓物質を用いたTAEの試み
    作原 祐介, 西尾 妙織, 阿保 大介, 曽山 武士, 三村 秀文, 工藤 與亮
    日本医学放射線学会秋季臨床大会抄録集 (公社)日本医学放射線学会 52回 S448 - S449 0048-0428 2016/08
  • ステアリングマイクロカテーテルが有用であった2例
    曽山 武士, 吉田 大介, 阿保 大介, 森田 亮, 作原 祐介, 工藤 與亮
    日本医学放射線学会秋季臨床大会抄録集 (公社)日本医学放射線学会 52回 S513 - S513 0048-0428 2016/08
  • Kohsuke Kudo, Tian Liu, Toshiyuki Murakami, Jonathan Goodwin, Ikuko Uwano, Fumio Yamashita, Satomi Higuchi, Yi Wang, Kuniaki Ogasawara, Akira Ogawa, Makoto Sasaki
    Journal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism 36 (8) 1424 - 33 0271-678X 2016/08 [Refereed][Not invited]
     
    The purposes of this study are to establish oxygen extraction fraction (OEF) measurements using quantitative susceptibility mapping (QSM) of magnetic resonance imaging (MRI), and to compare QSM-OEF data with the gold standard (15)O positron emission tomography (PET). Twenty-six patients with chronic unilateral internal carotid artery or middle cerebral artery stenosis or occlusion, and 15 normal subjects were included. MRI scans were conducted using a 3.0 Tesla scanner with a three-dimensional spoiled gradient recalled sequence. QSM images were created using the morphology-enabled dipole inversion method, and OEF maps were generated from QSM images using extraction of venous susceptibility induced by deoxygenated hemoglobin. Significant correlation of relative OEF ratio to contra-lateral hemisphere between QSM-OEF and PET-OEF was observed (r = 0.62, p < 0.001). The local (intra-section) correlation was also significant (r = 0.52, p < 0.001) in patients with increased PET-OEF. The sensitivity and specificity of OEF increase in QSM was 0.63 (5/8) and 0.89 (16/18), respectively, in comparison with PET. In conclusion, good correlation was achieved between QSM-OEF and PET-OEF in the identification of elevated OEF in affected hemispheres of patients with unilateral chronic steno-occlusive disease.
  • Takeshi Soyama, Yusuke Sakuhara, Kohsuke Kudo, Daisuke Abo, Jeff Wang, Yoichi M Ito, Yu Hasegawa, Hiroki Shirato
    Journal of medical ultrasonics (2001) 43 (3) 327 - 35 1346-4523 2016/07 [Refereed][Not invited]
     
    PURPOSE: This preliminary study compared ultrasonography-computed tomography (US-CT) fusion imaging and conventional ultrasonography (US) for accuracy and time required for target identification using a combination of real phantoms and sets of digitally modified computed tomography (CT) images (digital/real hybrid phantoms). METHODS: In this randomized prospective study, 27 spheres visible on B-mode US were placed at depths of 3.5, 8.5, and 13.5 cm (nine spheres each). All 27 spheres were digitally erased from the CT images, and a radiopaque sphere was digitally placed at each of the 27 locations to create 27 different sets of CT images. Twenty clinicians were instructed to identify the sphere target using US alone and fusion imaging. The accuracy of target identification of the two methods was compared using McNemar's test. The mean time required for target identification and error distances were compared using paired t tests. RESULTS: At all three depths, target identification was more accurate and the mean time required for target identification was significantly less with US-CT fusion imaging than with US alone, and the mean error distances were also shorter with US-CT fusion imaging. CONCLUSION: US-CT fusion imaging was superior to US alone in terms of accurate and rapid identification of target lesions.
  • Amplatzer vascular plug 4(AVP4)を用いた腹腔動脈瘤に対する塞栓術の経験
    木村 輔, 阿保 大介, 亀田 浩之, 高橋 文也, 曽山 武士, 作原 祐介, 工藤 與亮
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 31 (2) 175 - 175 1340-4520 2016/06
  • 子宮頸癌に対する放射線治療後の膀胱内出血に対しTAEを施行した1例
    曽山 武士, 作原 祐介, 木村 輔, 高橋 文也, 阿保 大介, 工藤 與亮
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 31 (2) 176 - 176 1340-4520 2016/06
  • Edwin Bennink, Jaap Oosterbroek, Kohsuke Kudo, Max A Viergever, Birgitta K Velthuis, Hugo W A M de Jong
    Journal of medical imaging (Bellingham, Wash.) 3 (2) 026003 - 026003 2329-4302 2016/04 [Refereed][Not invited]
     
    Although computed tomography (CT) perfusion (CTP) imaging enables rapid diagnosis and prognosis of ischemic stroke, current CTP analysis methods have several shortcomings. We propose a fast nonlinear regression method with a box-shaped model (boxNLR) that has important advantages over the current state-of-the-art method, block-circulant singular value decomposition (bSVD). These advantages include improved robustness to attenuation curve truncation, extensibility, and unified estimation of perfusion parameters. The method is compared with bSVD and with a commercial SVD-based method. The three methods were quantitatively evaluated by means of a digital perfusion phantom, described by Kudo et al. and qualitatively with the aid of 50 clinical CTP scans. All three methods yielded high Pearson correlation coefficients ([Formula: see text]) with the ground truth in the phantom. The boxNLR perfusion maps of the clinical scans showed higher correlation with bSVD than the perfusion maps from the commercial method. Furthermore, it was shown that boxNLR estimates are robust to noise, truncation, and tracer delay. The proposed method provides a fast and reliable way of estimating perfusion parameters from CTP scans. This suggests it could be a viable alternative to current commercial and academic methods.
  • Rie Mimura, Fumi Kato, Khin Khin Tha, Kohsuke Kudo, Yosuke Konno, Noriko Oyama-Manabe, Tatsuya Kato, Hidemichi Watari, Noriaki Sakuragi, Hiroki Shirato
    Japanese journal of radiology 34 (3) 229 - 37 1867-1071 2016/03 [Refereed][Not invited]
     
    PURPOSE: This study aimed to evaluate whether histogram analysis of the apparent diffusion coefficient (ADC) of a solid tumor component could distinguish borderline ovarian tumors from ovarian carcinoma. MATERIALS AND METHODS: Sixteen pathologically proven borderline tumors and 21 carcinomas were retrospectively examined. Magnetic resonance (1.5-T) image data sets were coregistered, and the solid components of each tumor were semiautomatically segmented. ADC histograms of the solid components were extracted; modes, minimums, means, and 10th, 25th, 50th, 75th, and 90th percentiles of the histograms were compared between the two tumor types, and receiver-operating characteristic (ROC) analysis was performed. RESULTS: The mode, minimum, mean, 10th, 25th, 50th, and 75th percentile ADC values of solid components of borderline tumors were significantly larger than those of carcinomas. Among these, the 10th percentile values had the lowest p value (p = 0.0003). At ROC analysis, the area under the curve (AUC) in the 10th percentile was the greatest (0.854), and the best cutoff value in the 10th percentile provided the highest specificity (93.8 %). CONCLUSIONS: ADC histograms of solid tumor components facilitated the distinction between borderline ovarian tumors and carcinoma. The 10th percentile ADC values had the best diagnostic performance.
  • Yuki Satoshi, Nakatsumi Hiroshi, Sawada Kentaro, Kato Takashi, Meguro Takashi, Nakamura Michio, Iwanaga Ichiro, Ehira Nobuyuki, Sonoda Norikazu, Kudo Mineo, Kato Kanji, Sogabe Susumu, Amano Toraji, Ono Kota, Sakamoto Keita, Miyamoto Noriyuki, Kudo Kohsuke, Sakamoto Naoya, Sakata Yuh, Komatsu Yoshito
    JOURNAL OF CLINICAL ONCOLOGY 34 (4) 0732-183X 2016/02/01 [Refereed][Not invited]
  • CTが診断に有用であった繰り返す消化管出血症例
    亀田 浩之, 真鍋 徳子, 菊池 穏香, 坂本 圭太, 三村 理恵, 加藤 扶美, 工藤 與亮, 藪崎 哲史, 宮本 憲幸, 西田 睦, 畑中 佳奈子, 大野 正芳, 高橋 典彦
    Japanese Journal of Radiology (公社)日本医学放射線学会 34 (Suppl.) 3 - 3 1867-1071 2016/02
  • Microballoon catheter併用で瘤内塞栓を施行した腎動脈瘤の2例
    吉野 裕紀, 阿保 大介, 曽山 武士, 打浪 雄介, 高橋 文也, 作原 祐介, 工藤 與亮
    Japanese Journal of Radiology (公社)日本医学放射線学会 34 (Suppl.) 4 - 4 1867-1071 2016/02
  • Microballoon catheterを用いたwedge techniqueによるNBCA塞栓術の初期経験 豚動脈を用いた実行可能性の検討
    阿保 大介, 高橋 文也, 吉野 裕紀, 打浪 雄介, 曽山 武士, 作原 祐介, 工藤 與亮
    Japanese Journal of Radiology (公社)日本医学放射線学会 34 (Suppl.) 4 - 4 1867-1071 2016/02
  • NBCAを用いて気管支動脈塞栓術を施行した大量喀血の1例
    吉野 裕紀, 阿保 大介, 高橋 文也, 菊池 穏香, 曽山 武士, 宮本 憲幸, 作原 祐介, 工藤 與亮, 中久保 祥, 在原 房子
    Japanese Journal of Radiology (公社)日本医学放射線学会 34 (Suppl.) 12 - 12 1867-1071 2016/02
  • N Fujima, D Yoshida, T Sakashita, A Homma, A Tsukahara, K K Tha, K Kudo, H Shirato
    AJNR. American journal of neuroradiology 37 (2) 342 - 8 2016/02 [Refereed][Not invited]
     
    BACKGROUND AND PURPOSE: For the assessment of the treatment response in non-surgical treatment, tumor blood flow provides the functional information of the tumor which is different from the morphological information such as tumor volume. The purpose of this study was to evaluate the diagnostic value of tumor blood flow values obtained by pseudocontinuous arterial spin-labeling in patients with head and neck squamous cell carcinoma. MATERIALS AND METHODS: Forty-one patients with head and neck squamous cell carcinoma were evaluated by using pseudocontinuous arterial spin-labeling. Quantitative tumor blood flow was calculated at the pretreatment and the early treatment periods in all the patients, and the percentage change of tumor blood flow between the two was calculated. At the early treatment period, based on their tumor volume reduction rate, we divided the patients into stable disease and partial response groups for a subgroup analysis. The local control or failure was confirmed either by histopathology or by radiologic evaluation within the follow-up. RESULTS: Pretreatment tumor blood flow in patients in the failure group was significantly lower than that in patients in the local control group. In the subgroup analysis of patients with stable disease, the percentage change of tumor blood flow was significantly larger (due to the tumor blood flow increase from pretreatment value) in the local control group than in the failure group. In addition, in patients with a partial response, the percentage change of tumor blood flow was significantly smaller (due to the tumor blood flow decrease from the pretreatment value) in the local control group than in the failure group. The accuracy for determination of the local control group or the failure group in pretreatment tumor blood flow was 0.83 and that in the combination use of the percentage change of tumor blood flow and tumor volume in the early treatment period was 0.93. CONCLUSIONS: Tumor blood flow obtained by pseudocontinuous arterial spin-labeling can be useful for the determination of local control. The combined use of the percentage change of tumor blood flow and tumor volume had particularly high diagnostic accuracy.
  • Yi Cui, Khin Khin Tha, Shunsuke Terasaka, Shigeru Yamaguchi, Jeff Wang, Kohsuke Kudo, Lei Xing, Hiroki Shirato, Ruijiang Li
    Radiology 278 (2) 546 - 53 0033-8419 2016/02 [Refereed][Not invited]
     
    PURPOSE: To develop and independently validate prognostic imaging biomarkers for predicting survival in patients with glioblastoma on the basis of multiregion quantitative image analysis. MATERIALS AND METHODS: This retrospective study was approved by the local institutional review board, and informed consent was waived. A total of 79 patients from two independent cohorts were included. The discovery and validation cohorts consisted of 46 and 33 patients with glioblastoma from the Cancer Imaging Archive (TCIA) and the local institution, respectively. Preoperative T1-weighted contrast material-enhanced and T2-weighted fluid-attenuation inversion recovery magnetic resonance (MR) images were analyzed. For each patient, we semiautomatically delineated the tumor and performed automated intratumor segmentation, dividing the tumor into spatially distinct subregions that demonstrate coherent intensity patterns across multiparametric MR imaging. Within each subregion and for the entire tumor, we extracted quantitative imaging features, including those that fully capture the differential contrast of multimodality MR imaging. A multivariate sparse Cox regression model was trained by using TCIA data and tested on the validation cohort. RESULTS: The optimal prognostic model identified five imaging biomarkers that quantified tumor surface area and intensity distributions of the tumor and its subregions. In the validation cohort, our prognostic model achieved a concordance index of 0.67 and significant stratification of overall survival by using the log-rank test (P = .018), which outperformed conventional prognostic factors, such as age (concordance index, 0.57; P = .389) and tumor volume (concordance index, 0.59; P = .409). CONCLUSION: The multiregion analysis presented here establishes a general strategy to effectively characterize intratumor heterogeneity manifested at multimodality imaging and has the potential to reveal useful prognostic imaging biomarkers in glioblastoma.
  • Suguru Yokosawa, Makoto Sasaki, Yoshitaka Bito, Kenji Ito, Fumio Yamashita, Jonathan Goodwin, Satomi Higuchi, Kohsuke Kudo
    Magnetic resonance in medical sciences : MRMS : an official journal of Japan Society of Magnetic Resonance in Medicine 15 (1) 41 - 8 1347-3182 2016 [Refereed][Not invited]
     
    PURPOSE: To shorten acquisition of diffusion kurtosis imaging (DKI) in 1.5-tesla magnetic resonance (MR) imaging, we investigated the effects of the number of b-values, diffusion direction, and number of signal averages (NSA) on the accuracy of DKI metrics. METHODS: We obtained 2 image datasets with 30 gradient directions, 6 b-values up to 2500 s/mm(2), and 2 signal averages from 5 healthy volunteers and generated DKI metrics, i.e., mean, axial, and radial kurtosis (MK, K∥, and K⊥) maps, from various combinations of the datasets. These maps were estimated by using the intraclass correlation coefficient (ICC) with those from the full datasets. RESULTS: The MK and K⊥ maps generated from the datasets including only the b-value of 2500 s/mm(2) showed excellent agreement (ICC, 0.96 to 0.99). Under the same acquisition time and diffusion directions, agreement was better of MK, K∥, and K⊥ maps obtained with 3 b-values (0, 1000, and 2500 s/mm(2)) and 4 signal averages than maps obtained with any other combination of numbers of b-value and varied NSA. Good agreement (ICC > 0.6) required at least 20 diffusion directions in all the metrics. CONCLUSION: MK and K⊥ maps with ICC greater than 0.95 can be obtained at 1.5T within 10 min (b-value = 0, 1000, and 2500 s/mm(2); 20 diffusion directions; 4 signal averages; slice thickness, 6 mm with no interslice gap; number of slices, 12).
  • Noriyuki Fujima, Tomohiro Sakashita, Akihiro Homma, Kenji Hirata, Tohru Shiga, Kohsuke Kudo, Hiroki Shirato
    PloS one 11 (11) e0166236  1932-6203 2016 [Refereed][Not invited]
     
    OBJECTIVE: To determine the relationship between tumor glucose metabolism and tumor blood flow (TBF) in head and neck squamous cell carcinoma (HNSCC). METHODS: We retrospectively analyzed 57 HNSCC patients. Tumor glucose metabolism was assessed by maximum and mean standardized uptake values (SUVmax and SUVmean) obtained by 18F-fluorodeoxyglucose positron-emission tomography. TBF values were obtained by arterial spin labeling with 3-tesla MRI. The correlations between both SUVs and TBF were assessed in the total series and among patients divided by T-stage (T1-T3 and T4 groups) and tumor location (pharynx/oral cavity and sinonasal cavity groups). Pearson's correlation coefficients were calculated for significant correlations. RESULTS: Significant correlations were detected: a negative correlation in the advanced T-stage group (TBF and SUV max: r, -0.61, SUVmean: r, -0.62), a positive correlation in the non-advanced T-stage pharynx/oral cavity group (TBF and SUVmax: r, 0.70, SUVmean: r, 0.73), a negative correlation in the advanced T-stage pharynx/oral cavity group (TBF and SUVmax: r, -0.62, SUVmean: r, -0.65), and a negative correlation in the advanced T-stage sinonasal cavity group (TBF and SUVmax: r, -0.61, SUVmean: r, -0.65). CONCLUSION: Significant correlations between glucose uptake and TBF in HNSCC were revealed by the division of T-stage and tumor location.
  • Chengbo Tan, Hideo Shichinohe, Zifeng Wang, Shuji Hamauchi, Takeo Abumiya, Naoki Nakayama, Ken Kazumata, Tsuneo Ito, Kohsuke Kudo, Shigeru Takamoto, Kiyohiro Houkin
    Stem cells international 2016 6104780 - 6104780 1687-966X 2016 [Refereed][Not invited]
     
    Currently, there is increasing interest in human bone marrow stromal cells (hBMSCs) as regeneration therapy against cerebral stroke. The aim of the present study was to evaluate the feasibility and validity of hBMSC cultures with allogeneic platelet lysates (PLs). Platelet concentrates (PC) were harvested from healthy volunteers and made into single donor-derived PL (sPL). The PL mixtures (mPL) were made from three different sPL. Some growth factors and platelet cell surface antigens were detected by enzyme-linked immunosorbent assay (ELISA). The hBMSCs cultured with 10% PL were analyzed for their proliferative potential, surface markers, and karyotypes. The cells were incubated with superparamagnetic iron oxide (SPIO) agents and injected into a pig brain. MRI and histological analysis were performed. Consequently, nine lots of sPL and three mPL were prepared. ELISA analysis showed that PL contained adequate growth factors and a particle of platelet surface antigens. Cell proliferation capacity of PLs was equivalent to or higher than that of fetal calf serum (FCS). No contradiction in cell surface markers and no chromosomal aberrations were found. The MRI detected the distribution of SPIO-labeled hBMSCs in the pig brain. In summary, the hBMSCs cultured with allogeneic PL are suitable for cell therapy against stroke.
  • Takashi Ohno, Kohsuke Kudo, Greg Zaharchuk, Noriyuki Fujima, Hiroki Shirato
    Japanese journal of radiology 34 (1) 28 - 34 1867-1071 2016/01 [Refereed][Not invited]
     
    PURPOSE: The purpose of the present study was to determine optimal threshold of vascular pixel elimination (VPE) for CT perfusion (CTP) and to assess diagnostic accuracy of CTP by comparing with xenon enhanced CT (XeCT) in moyamoya disease. MATERIALS AND METHODS: Twenty-three patients underwent XeCT and CTP. Cerebral blood flow (CBF) images were generated for XeCT and CTP using nine types of software. Region of interest (ROI) measurement was performed on XeCT-CBF and CTP-CBF. Linear regression analysis was performed between XeCT-CBF and CTP-CBF in all software, without and with VPE. The Pearson correlation coefficient was calculated, and an optimal threshold was determined based on maximum correlation coefficients. Correlation coefficients at various VPE thresholds including data of no-VPE were compared with each other. The maximum correlation coefficient at the optimal threshold was also compared. RESULTS: Optimal thresholds varied among software types (0.8-2.2 and 7-14 ml/100 g in relative and absolute VPE, respectively). There were significant differences between correlation coefficients at a range of VPE thresholds compared to no-VPE in most software types. There were significant differences in maximum correlation coefficient at optimal threshold among various software types. CONCLUSION: Optimal threshold of VPE for CTP could be determined and diagnostic accuracy of CTP varied among software types in moyamoya disease.
  • Fumi Kato, Kohsuke Kudo, Hiroko Yamashita, Jeff Wang, Mitsuchika Hosoda, Kanako C Hatanaka, Rie Mimura, Noriko Oyama-Manabe, Hiroki Shirato
    European journal of radiology 85 (1) 96 - 102 0720-048X 2016/01 [Refereed][Not invited]
     
    PURPOSE: To compare the morphology and minimum apparent diffusion coefficient (ADC) values among breast cancer subtypes. METHODS: Ninety-three patients, who underwent breast MRI and collectively had 98 pathologically proven invasive carcinomas, were enrolled. Morphology was evaluated according to BIRADS-MRI. Minimum ADC was measured. Morphology and minimum ADC were compared among subtypes. Multivariate logistic regression analyses were used to identify the characteristics associated with different subtypes. RESULTS: Oval/round shape was significantly associated with triple-negative (TN) cancer (TN vs. non-TN: 90.9% vs. 45.2%; p=0.0123). Rim enhancement was significantly less frequent in Luminal A (Luminal A vs. non-Luminal A: 34.2% vs. 76.1%; p=0.0003). The minimum ADC of Luminal A was significantly higher than that of Luminal B (HER2-negative) (834 vs. 748×10(-6)mm(2)/s; p<0.025). The minimum ADC of the TN-special type was significantly higher than that of TN-ductal (997 vs. 702×10(-6)mm(2)/s; p<0.025). On the multivariate analysis comparing the characteristics associated with Luminal A vs. Luminal B (HER2-negative), the internal enhancement characteristics of the mass and minimum ADC were significant factors. CONCLUSION: Morphology and minimum ADC would be useful in distinguishing breast cancer subtypes.
  • Hiroyuki Sugimori, Noriyuki Fujima, Yuriko Suzuki, Hiroyuki Hamaguchi, Motomichi Sakata, Kohsuke Kudo
    Magnetic resonance imaging 33 (10) 1338 - 1344 0730-725X 2015/12 [Refereed][Not invited]
     
    PURPOSE: Arterial spin labeling (ASL) methods have been widely used for evaluation of cerebral blood flow (CBF) by magnetic resonance imaging. However, ASL methods require setting of the post labeling delay (PLD) time for obtaining images. As the hemodynamic status cannot be estimated in each patient, the resultant quantitative values of blood flow may not be accurate. The multi-phase pseudo continuous arterial spin labeling (pCASL) method can be used to obtain images at various time-points. The purpose of this study was to create the transit-time maps for correcting the delayed blood flow and evaluate CBF using the transit-time maps obtained by the multi-phase pCASL method. MATERIALS AND METHODS: Twelve patients who underwent both 3.0-tesla magnetic resonance imaging (MRI) and single photon emission computed tomography with iodine-123-N-isopropyl-p-iodoamphetamine (123I-IMP) were investigated. This study was approved by the institutional review board of our institution. MRI acquisitions included PLD time-fixed (1525ms) and multi-phase pCASL sequences. The transit-time maps were calculated from multi-phase pCASL images by software. The transit-time maps were applied to PLD-fixed pCASL images pixel by pixel, for calculating the CBF value corrected for peak blood transit time. Regions of interest were drawn on the brain. IMP-CBF, ASL-CBF (default and corrected) and transit time were measured for each segment. RESULTS: Twelve patients and 264 segments were investigated. The mean IMP-CBF, ASL-CBF (default, corrected) and transit time were 28.4, 23.0, 29.6, [ml/min/100g] and 1977.5 [ms], respectively. There were no significant differences between IMP-CBF and ASL-CBF (corrected). CONCLUSION: CBF values can be corrected by using the transit-time maps obtained using the multi-phase pCASL method.
  • Noriyuki Fujima, Hiroyuki Kameda, Akiko Tsukahara, Daisuke Yoshida, Tomohiro Sakashita, Akihiro Homma, Khin Khin Tha, Kohsuke Kudo, Hiroki Shirato
    European journal of radiology 84 (11) 2187 - 93 0720-048X 2015/11 [Refereed][Not invited]
     
    OBJECTIVES: To investigate the diagnostic value of tumor blood flow (TBF) obtained with pseudo-continuous arterial spin labeling (pCASL) for the differentiation of squamous cell carcinoma (SCC) and malignant lymphoma (ML) in the nasal or sinonasal cavity. METHODS: Thirty-three patients with SCC and 6 patients with ML in the nasal or sinonasal cavity were retrospectively analyzed. Quantitative TBF values were obtained using whole-tumor region of interest (ROI) from pCASL data. The histogram analysis of TBF values within the tumor ROI was also performed by calculating the coefficient of variation (CV), kurtosis, and skewness. The mean TBF value, histogram CV, kurtosis and skewness of the patients with SCC were compared with those of the ML patients. The diagnostic accuracy to differentiate SCC from ML was also calculated by receiver operating characteristic (ROC) curve analysis. In addition, multiple logistic regression models were also performed to determine their independent predictive value, and diagnostic accuracy with the combined use of these parameters. RESULTS: Between the SCC and ML groups, significant differences were observed in mean TBF, CV, and kurtosis, but not in skewness. In ROC curve analysis, the diagnostic accuracy values for the differentiation of SCC from ML in mean TBF, CV, and kurtosis were all 0.87, respectively. Multiple logistic regression models revealed TBF and CV were respectively independent predictive value. With the combination of these parameters, the diagnostic accuracy was elevated to 0.97. CONCLUSIONS: The TBF value and its histogram analysis obtained with pCASL can help differentiate SCC and ML.
  • 【神経放射線診断-最新情報と読影のピットフォール】MRI Perfusion MRI Arterial spin labeling(ASL)とdynamic susceptibility contrast(DSC)を中心に
    清水 幸衣, 工藤 與亮, 藤間 憲幸
    Clinical Neuroscience (株)中外医学社 33 (10) 1125 - 1128 0289-0585 2015/10
  • Yusuke Sakuhara, Saori Nishio, Ken Morita, Daisuke Abo, Yu Hasegawa, Noriaki Yuasa, Toshio Mochizuki, Takeshi Soyama, Koji Oba, Hiroki Shirato, Kohsuke Kudo
    Radiology 277 (1) 277 - 85 0033-8419 2015/10 [Refereed][Not invited]
     
    PURPOSE: To evaluate the safety and effectiveness of transcatheter arterial embolization (TAE) with ethanol in symptomatic patients with enlarged polycystic kidney disease. MATERIALS AND METHODS: This prospective study was institutional review board approved and was planned for patients with symptoms related to enlarged polycystic kidney disease, such as a markedly distended abdomen, gastroesophageal reflux, and abdominal pain. At the time of TAE, all patients were undergoing dialysis therapy for chronic renal failure, and their urinary volume had decreased to less than 500 mL per day. Bilateral renal TAE with absolute ethanol was performed, and changes in kidney volume, clinical symptoms, laboratory data, and complications were evaluated after TAE. The differences in patients' kidney volumes, clinical symptoms, abdominal circumference, and dry weights before and after TAE were analyzed with a mixed effect model. RESULTS: Fifteen patients (seven men and eight women; mean age, 57.7 years ± 5.3 [standard deviation]) were treated. Among the 15 patients, the follow-up period was 24 months in 13 patients, 6 months in one patient, and 3 months in one patient. The mean kidney volume was 3380 mL before renal TAE, and at 3, 12, and 24 months after TAE, it significantly decreased to 60.9%, 39.8%, and 32.1% of the pretherapeutic value, respectively (P < .001). All patients reported improved clinical symptoms within 3 months after TAE (P < .001). Abdominal circumferences were significantly decreased after TAE (P < .001). The dry weights also continued to significantly decreased until 6 months after TAE (P < .001), at which point they began to slightly increase until 24 months after TAE. Abdominal pain, nausea, and inflammatory response developed in all patients after TAE, but these symptoms improved with conservative treatment. Abscess formation was found in one kidney, and drainage catheter placement was performed. No major complications related to TAE occurred in the remaining patients. CONCLUSION: Renal contraction therapy by TAE with ethanol injection appears to be a safe and effective treatment in patients with symptomatic enlarged polycystic kidney disease.
  • Taisuke Harada, Takashige Abe, Fumi Kato, Ryuji Matsumoto, Hiromi Fujita, Sachiyo Murai, Naoto Miyajima, Kunihiko Tsuchiya, Satoru Maruyama, Kohsuke Kudo, Nobuo Shinohara
    BMC urology 15 91 - 91 1471-2490 2015/09/04 [Refereed][Not invited]
     
    BACKGROUND: To clarify the relationship between the probability of prostate cancer scaled using a 5-point Likert system and the biological characteristics of corresponding tumor foci. METHODS: The present study involved 44 patients undergoing 3.0-Tesla multiparametric MRI before laparoscopic radical prostatectomy. Tracing based on pathological and MRI findings was performed. The relationship between the probability of cancer scaled using the 5-point Likert system and the biological characteristics of corresponding tumor foci was evaluated. RESULTS: A total of 102 tumor foci were identified histologically from the 44 specimens. Of the 102 tumors, 55 were assigned a score based on MRI findings (score 1: n = 3; score 2: n = 3; score 3: n = 16; score 4: n = 11 score 5: n = 22), while 47 were not pointed out on MRI. The tracing study revealed that the proportion of >0.5 cm(3) tumors increased according to the upgrade of Likert scores (score 1 or 2: 33%; score 3: 68.8%; score 4 or 5: 90.9%, χ(2) test, p < 0.0001). The proportion with a Gleason score >7 also increased from scale 2 to scale 5 (scale 2: 0%; scale 3: 56.3%; scale 4: 72.7%; 5: 90.9%, χ(2) test, p = 0.0001). On using score 3 or higher as the threshold of cancer detection on MRI, the detection rate markedly improved if the tumor volume exceeded 0.5 cm(3) (<0.2 cm(3): 10.3%; 0.2-0.5 cm(3): 25%; 0.5-1.0 cm(3): 66.7%; 1.0 < cm(3): 92.1%). CONCLUSIONS: Each Likert scale favobably reflected the corresponding tumor's volume and Gleason score. Our observations show that "score 3 or higher" could be a useful threshold to predict clinically significant carcinoma when considering treatment options.
  • 上腸間膜動脈狭窄による慢性腸管虚血に対し経皮的血管形成術を施行した1例
    曽山 武士, 阿保 大介, 作原 祐介, 高橋 文也, 工藤 與亮
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 30 (3) 269 - 269 1340-4520 2015/09
  • 内腔.038inchカテーテル対応マイクロバルーンカテーテルによるバルーンアシスト法併用でTAEを施行した腎動脈瘤の1例
    阿保 大介, 高橋 文也, 曽山 武士, 作原 祐介, 工藤 與亮
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 30 (3) 269 - 270 1340-4520 2015/09
  • 腎部分切除術後出血・仮性動脈瘤に対するTAE症例の検討
    阿保 大介, 作原 祐介, 曽山 武士, 高橋 文也, 工藤 與亮, 安部 崇重, 丸山 覚, 森田 研, 篠原 信雄, 野々村 克也
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 30 (3) 270 - 270 1340-4520 2015/09
  • 真性内臓動脈瘤に対するTAE症例の検討
    高橋 文也, 阿保 大介, 作原 祐介, 曽山 武士, 工藤 與亮
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 30 (3) 270 - 270 1340-4520 2015/09
  • 多発性肝嚢胞に対するEmbosphereを用いた肝動脈塞栓術の初期経験
    作原 祐介, 曽山 武士, 高橋 文也, 阿保 大介, 工藤 與亮, 西尾 妙織, 三村 秀文
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 30 (3) 270 - 270 1340-4520 2015/09
  • NBCAを用いて気管支動脈塞栓術を施行した大量喀血の1例
    吉野 裕紀, 阿保 大介, 高橋 文也, 菊池 穏香, 曽山 武士, 作原 祐介, 工藤 與亮, 中久保 祥, 在原 房子
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 30 (3) 272 - 272 1340-4520 2015/09
  • 腹部大動脈ステントグラフト内挿術後のタイプIIエンドリークに対し、Penumbra Coilを用い塞栓術を行った1例
    高橋 文也, 作原 祐介, 吉野 裕紀, 曽山 武士, 阿保 大介, 工藤 與亮, 新宮 康栄, 松居 喜郎
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 30 (3) 273 - 273 1340-4520 2015/09
  • Microballoon catheterを用いたwedge techniqueによるNBCA塞栓術の初期経験
    阿保 大介, 高橋 文也, 曽山 武士, 作原 祐介, 工藤 與亮
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 30 (3) 273 - 273 1340-4520 2015/09
  • 胃GIST肝転移に対してbland TAEを施行した1例
    作原 祐介, 吉野 裕紀, 阿保 大介, 曽山 武士, 菊地 穏香, 高橋 文也, 工藤 與亮
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 30 (3) 274 - 274 1340-4520 2015/09
  • 多発性嚢胞腎に対するエタノールを用いた腎動脈塞栓療法
    作原 祐介, 阿保 大介, 曽山 武士, 高橋 文也, 工藤 與亮, 西尾 妙織, 森田 研, 長谷川 悠, 湯浅 憲章
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 30 (3) 274 - 274 1340-4520 2015/09
  • Yuuki Tomiyama, Osamu Manabe, Noriko Oyama-Manabe, Masanao Naya, Hiroyuki Sugimori, Kenji Hirata, Yuki Mori, Hiroyuki Tsutsui, Kohsuke Kudo, Nagara Tamaki, Chietsugu Katoh
    Journal of magnetic resonance imaging : JMRI 42 (3) 754 - 62 1053-1807 2015/09 [Refereed][Not invited]
     
    BACKGROUND: To develop and validate a method for quantifying myocardial blood flow (MBF) using dynamic perfusion magnetic resonance imaging (MBFMRI ) at 3.0 Tesla (T) and compare the findings with those of (15) O-water positron emission tomography (MBFPET ). METHODS: Twenty healthy male volunteers underwent magnetic resonance imaging (MRI) and (15) O-water positron emission tomography (PET) at rest and during adenosine triphosphate infusion. The single-tissue compartment model was used to estimate the inflow rate constant (K1). We estimated the extraction fraction of Gd-DTPA using K1 and MBF values obtained from (15) O-water PET for the first 10 subjects. For validation, we calculated MBFMRI values for the remaining 10 subjects and compared them with the MBFPET values. In addition, we compared MBFMRI values of 10 patients with coronary artery disease with those of healthy subjects. RESULTS: The mean resting and stress MBFMRI values were 0.76 ± 0.10 and 3.04 ± 0.82 mL/min/g, respectively, and showed excellent correlation with the mean MBFPET values (r = 0.96, P < 0.01). The mean stress MBFMRI value was significantly lower for the patients (1.92 ± 0.37) than for the healthy subjects (P < 0.001). CONCLUSION: The use of dynamic perfusion MRI at 3T is useful for estimating MBF and can be applied for patients with coronary artery disease.
  • Susumu Shibasaki, Norihiko Takahashi, Shigenori Homma, Mutsumi Nishida, Tatsushi Shimokuni, Tadashi Yoshida, Hideki Kawamura, Noriko Oyama-Manabe, Kohsuke Kudo, Akinobu Taketomi
    Abdominal imaging 40 (6) 1441 - 50 0942-8925 2015/08 [Refereed][Not invited]
     
    PURPOSE: Although noninvasive and highly informative, transabdominal ultrasonography (US) is not yet an accepted means of staging colorectal cancer preoperatively. This prospective study evaluated the diagnostic accuracy of US in preoperative staging of patients with resectable colon cancers. METHODS: A total of 98 patients with primary colon cancer diagnosed by colonoscopy at our institute between January, 2011 and June, 2014 underwent preoperative ultrasonographic tumor staging. Depth of tumor infiltration (T-stage) was assessed by standard means (i.e., extent of mural involvement), analyzing agreement in US and histopathology determinations. RESULTS: All but two colon cancers (at splenic flexure) were detected by US (98%, 96/98). Compared with histopathology, overall accuracy of US in determining T-stage was 64% (61/96), indicating moderate reproducibility (κ coefficient 0.48; 95% CI 0.35-0.62; p < 0.001). Using a three-tier approach of graded muscularis propria (MP) involvement (Tis/T1, below MP; T2, within MP; and T3/T4, beyond MP), diagnostic agreement increased to 89% (85/96), with good agreement (κ coefficient 0.77; 95% CI 0.64-0.90; p < 0.001). No tumor characteristics or patient demographics influenced diagnostic agreement at any site in the colon. CONCLUSIONS: Given the potential to yield valuable information while limiting patient discomfort, US should be reconsidered as a means of assessing colon cancer.
  • Jonathan A. Goodwin, Kohsuke Kudo, Yutaka Shinohe, Satomi Higuchi, Ikuko Uwano, Fumio Yamashita, Makoto Sasaki
    JOURNAL OF NEUROIMAGING 25 (4) 575 - 581 1051-2284 2015/07 [Refereed][Not invited]
     
    BACKGROUND & PURPOSEIn this work, we demonstrate oxygen extraction fraction (OEF) measurement using 7T MRI with susceptibility-weighted imaging (SWI), in sedated and nonsedated adults. METHODSTen healthy subjects (30.3 4.5 years, 9 men, 1 woman) formed control (n = 5) and sedation groups (n = 5). Midazolam and propofol injection was administered to the same sedation group subjects during 2 different scanning sessions. Two-dimensional SPGR imaging was performed before, during, and twice after (propofol, +10, +30 minutes; midazolam, +10, +40 minutes) conscious sedation. The equivalent procedure was performed with the control group without sedation. After SWI analysis, change in OEF between scans was quantified, and parcelated OEF maps were generated with 77 gray matter (GM)-containing volumes-of-interest (VOIs). RESULTSSignificant decreases in OEF were shown in 14 GM VOIs during sedation relative to the control group, most notably during midazolam sedation (P < .05). In contrast, no significant decrease was observed after 10 minutes and in only 4 VOIs after 40 minutes recovery. CONCLUSIONSignificant change in OEF during conscious sedation using midazolam and propofol could be measured using SWI at 7T in vivo. This may be a potentially useful approach for the noninvasive assessment of OEF in the brain on a clinical basis.
  • Max Wintermark, Marie Luby, Natan M Bornstein, Andrew Demchuk, Jens Fiehler, Kohsuke Kudo, Kennedy R Lees, David S Liebeskind, Patrik Michel, Raul G Nogueira, Mark W Parsons, Makoto Sasaki, Joanna M Wardlaw, Ona Wu, Weiwei Zhang, Guangming Zhu, Steven J Warach
    International journal of stroke : official journal of the International Stroke Society 10 (5) 759 - 62 1747-4930 2015/07 [Refereed][Not invited]
     
    BACKGROUND: To assess the differences across continental regions in terms of stroke imaging obtained for making acute revascularization therapy decisions, and to identify obstacles to participating in randomized trials involving multimodal imaging. METHODS: STroke Imaging Repository (STIR) and Virtual International Stroke Trials Archive (VISTA)-Imaging circulated an online survey through its website, through the websites of national professional societies from multiple countries as well as through email distribution lists from STIR and the above mentioned societies. RESULTS: We received responses from 223 centers (2 from Africa, 38 from Asia, 10 from Australia, 101 from Europe, 4 from Middle East, 55 from North America, 13 from South America). In combination, the sites surveyed administered acute revascularization therapy to a total of 25,326 acute stroke patients in 2012. Seventy-three percent of these patients received intravenous (i.v.) tissue plasminogen activator (tPA), and 27%, endovascular therapy. Vascular imaging was routinely obtained in 79% (152/193) of sites for endovascular therapy decisions, and also as part of standard IV tPA treatment decisions at 46% (92/198) of sites. Modality, availability and use of acute vascular and perfusion imaging before revascularization varied substantially between geographical areas. The main obstacles to participate in randomized trials involving multimodal imaging included: mainly insufficient research support and staff (50%, 79/158) and infrequent use of multimodal imaging (27%, 43/158) . CONCLUSION: There were significant variations among sites and geographical areas in terms of stroke imaging work-up used tomake decisions both for intravenous and endovascular revascularization. Clinical trials using advanced imaging as a selection tool for acute revascularization therapy should address the need for additional resources and technical support, and take into consideration the lack of routine use of such techniques in trial planning.
  • Noriyuki Fujima, Kohsuke Kudo, Akiko Tsukahara, Daisuke Yoshida, Tomohiro Sakashita, Akihiro Homma, Khin Khin Tha, Hiroki Shirato
    Journal of magnetic resonance imaging : JMRI 41 (4) 983 - 91 1053-1807 2015/04 [Refereed][Not invited]
     
    PURPOSE: To investigate the feasibility of tumor blood flow (TBF) measurement in head and neck squamous cell carcinoma (HNSCC) using pseudo-continuous arterial spin labeling (pCASL) in a comparison with dynamic contrast-enhanced (DCE) perfusion. MATERIALS AND METHODS: We prospectively scanned 18 patients with HNSCC using 3T magnetic resonance imaging (MRI) with both pCASL and DCE perfusion. Quantitative TBF value in the whole-tumor region of interest (ROI), and regional TBF in the ROIs of the central and peripheral areas in the tumor were respectively measured. Relative TBF value in the whole-tumor ROI was also calculated. We determined the correlation and agreement between each measured TBF by pCASL and DCE perfusion using Pearson's correlation coefficients, intraclass correlation coefficients (ICC), and Bland-Altman analysis. RESULTS: In the whole-tumor ROIs, significant correlation was observed between the absolute TBF values (r = 0.72, P < 0.01), with an ICC of 0.72; moreover, higher correlation was observed in the relative TBF (r = 0.79). The correlation was higher in the peripheral ROI (r = 0.70) than the central ROI (r = 0.65), with an ICC of 0.62 and 0.54, respectively. Bland-Altman plots revealed the underestimation of TBF by pCASL in central ROIs. CONCLUSION: TBF measurement by pCASL was feasible in patients with HNSCC.
  • Ito Kenji, Sasaki Makoto, Takahashi Junko, Uwano Ikuko, Yamashita Fumio, Higuchi Satomi, Goodwin Jonathan, Harada Taisuke, Kudo Kohsuke, Terayama Yasuo
    PSYCHIATRY RESEARCH-NEUROIMAGING 231 (3) 346 - 352 0925-4927 2015/03/30 [Refereed][Not invited]
  • Kenji Ito, Makoto Sasaki, Junko Takahashi, Ikuko Uwano, Fumio Yamashita, Satomi Higuchi, Jonathan Goodwin, Taisuke Harada, Kohsuke Kudo, Yasuo Terayama
    Psychiatry research 231 (3) 346 - 52 0165-1781 2015/03/30 [Refereed][Not invited]
     
    We aimed to determine alterations occurring in the parahippocampal cingulum bundle (PhC) and posterior cingulum bundle (PoC) in patients with mild cognitive impairment (MCI) through analysis of high-resolution multi-parametric diffusion tensor imaging (DTI). Participants comprised 41 patients with MCI (21 AD converters [MCI-C] and 20 non-converters [MCI-NC]), 20 patients with Alzheimer׳s disease (AD), and 26 healthy elderly subjects who underwent prospective examination with high-resolution DTI. An atlas-based regions-of-interest (ROIs) method calculated fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (DA), and radial diffusivity (DR) in the PhC and PoC. For the PhC, FA values showed significant decreases, and MD and DR values showed significantly increases, in the MCI-C and AD groups compared with the healthy controls, although the MCI-C and MCI-NC groups did not differ significantly in these metrics. Conversely, none of the diffusion metrics for the PoC showed a significant difference among the MCI groups and the control groups, although there were significant differences between the AD group and control groups. High-resolution multi-parametric DTI analysis was able to detect substantial changes in diffusion anisotropy and diffusivity in the PhC of patients with MCI who were destined to convert to AD.
  • Junko Takahashi, Toshihide Shibata, Makoto Sasaki, Masako Kudo, Hisashi Yanezawa, Satoko Obara, Kohsuke Kudo, Kenji Ito, Fumio Yamashita, Yasuo Terayama
    Geriatrics & gerontology international 15 (3) 334 - 40 1444-1586 2015/03 [Refereed][Not invited]
     
    AIM: Neuronal degeneration in the locus coeruleus occurs in the early phase of Alzheimer's disease, similar to mild cognitive impairment. The locus coeruleus produces norepinephrine, a deficiency of which causes both memory disturbance and psychological symptoms. Thus, we evaluated signal alterations in the locus coeruleus of patients with Alzheimer's disease and mild cognitive impairment using a high-resolution fast spin-echo T1-weighted imaging. METHODS: A total of 22 patients with Alzheimer's disease, 47 patients with mild cognitive impairment and 26 healthy controls were prospectively examined by high-resolution fast spin-echo T1-weighted imaging at 3 Tesla. Signal intensities in the locus coeruleus were manually measured and expressed relative to those in the adjacent white matter structures as contrast ratios. RESULTS: Locus coeruleus contrast ratios were significantly reduced in patient groups with Alzheimer's disease, mild cognitive impairment that converted to Alzheimer's disease and mild cognitive impairment that did not convert to Alzheimer's disease (1.80-16.09% [median, 9.30%], 3.45-14.84% [median 6.87%] and 3.01-19.19% [median 7.72%], respectively) compared with the healthy control group (6.24-20.94% [median 14.35%]; P < 0.0001). The sensitivity and specificity for discriminating these diseases were 85.0% and 69.2%, respectively, which suggests that this measurement can be carried out reliably. There was no significant difference in the locus coeruleus contrast ratios among the Alzheimer's disease, mild cognitive impairment-converted and mild cognitive impairment-non-converted groups. CONCLUSIONS: High-resolution fast spin-echo T1-weighted imaging can show signal attenuation in the locus coeruleus of patients with Alzheimer's disease or with mild cognitive impairment whose pathology may or may not eventually convert to Alzheimer's disease.
  • 3T MRIを用いた浸潤性乳癌の拡散尖度画像の検討 腋窩リンパ節転移予測における有用性(Diffusion kurtosis imaging at 3T MRI for invasive breast cancer: prediction of axillary lymph node metastasis)
    Kato Fumi, Kudo Kohsuke, Fujiwara Taro, Wang Jeff, Sugimori Hiroyuki, Yamashita Hiroko, Hosoda Mitsuchika, Mimura Rie, Miyamoto Noriyuki, Manabe Noriko
    日本医学放射線学会学術集会抄録集 74回 S190 - S191 0048-0428 2015/02
  • 3T心臓パーフュージョンMRIを用いた心筋血流定量法の確立(How to quantify cardiac perfusion MRI at 3 tesla in comparison with water PET)
    Manabe Noriko, Tomiyama Yuuki, Manabe Osamu, Katoh Chietsugu, Sugimori Hiroyuki, Kikuchi Yasuka, Kato Fumi, Kudo Kohsuke, Miyamoto Noriyuki, Nagara Tamaki
    日本医学放射線学会学術集会抄録集 74回 S289 - S289 0048-0428 2015/02
  • 頭頸部における扁平上皮癌と悪性リンパ腫の腫瘍血流の違い
    亀田 浩之, 藤間 憲幸, 吉川 仁人, 吉田 篤司, 清水 幸衣, 吉田 大介, 塚原 亜希子, 工藤 與亮, Tha Khin Khin, 白土 博樹
    Japanese Journal of Radiology (公社)日本医学放射線学会 33 (Suppl.) 1 - 1 1867-1071 2015/02
  • 発熱と骨病変が先行した小児白血病の1例
    藪崎 哲史, 宮本 憲幸, 白土 博樹, 真鍋 徳子, 藤間 憲幸, 菊池 穏香, 坂本 圭太, 三村 理恵, 加藤 芙美, 工藤 與亮, 佐藤 智信, 長 祐子, 井口 晶裕
    Japanese Journal of Radiology (公社)日本医学放射線学会 33 (Suppl.) 2 - 2 1867-1071 2015/02
  • 孤発性筋萎縮性側索硬化症における上行性感覚路のDTI解析
    清水 幸衣, 藤間 憲幸, 塚原 亜希子, 工藤 與亮, 矢部 一郎, 廣谷 真, 佐々木 秀直, Tha KhinKhin, 白土 博樹
    Japanese Journal of Radiology (公社)日本医学放射線学会 33 (Suppl.) 9 - 9 1867-1071 2015/02
  • 肝内門脈-静脈シャントによる高アンモニア血症に対して塞栓術が著効した1例
    高橋 文也, 作原 祐介, 薮崎 哲史, 阿保 大介, 曽山 武士, 工藤 與亮, 白土 博樹, 米澤 和彦
    Japanese Journal of Radiology (公社)日本医学放射線学会 33 (Suppl.) 6 - 6 1867-1071 2015/02
  • Takeo Abumiya, Noriyuki Fujima, Kohsuke Kudo, Yukitomo Ishi, Masayuki Gekka, Hideo Shichinohe, Ken Kazumata, Naoki Nakayama, Kiyohiro Houkin
    STROKE 46 0039-2499 2015/02 [Refereed][Not invited]
  • Noriyuki Miyamoto, Satoshi Yabusaki, Keita Sakamoto, Yasuka Kikuchi, Rie Mimura, Fumi Kato, Noriko Oyama-Manabe, Bunya Takahashi, Takeshi Soyama, Daisuke Abo, Yusuke Sakuhara, Kohsuke Kudo, Hiroki Shirato, Toru Nakamura, Takahiro Tsuchikawa, Keisuke Okamura, Satoshi Hirano
    Japanese journal of radiology 33 (2) 59 - 66 1867-1071 2015/02 [Refereed][Not invited]
     
    PURPOSE: To determine whether the preoperative pancreatic apparent diffusion coefficient (ADC) can be used to predict the development of postoperative pancreatic anastomotic failure (PAF). MATERIALS AND METHODS: We retrospectively examined the cases of 79 patients who underwent pancreatic head resection between January 2010 and October 2013. The patients underwent 1.5-T MR imaging including diffusion-weighted imaging before surgery. The main pancreatic duct diameter (MPD), the pancreatic parenchymal thickness (PT), and the ADC of the pancreatic remnant parenchyma were measured. Two radiologists blinded to the patients' outcomes performed the measurements. The imaging parameters were compared between the patients who developed PAF and those who did not. The cut-off ADC for the development of PAF was calculated with a receiver operating characteristic analysis. RESULTS: The imaging parameters were highly correlated between the two observers. The MPD and PT did not differ significantly among the patients. The mean pancreatic ADCs were significantly higher in the patients with PAF than in those without PAF. An ADC higher than 1.50 × 10(-3) mm(2)/s (Az = 0.719, observer-1) or 1.35 × 10(-3) mm(2)/s (Az = 0.752, observer-2) was optimal for predicting the development of postoperative PAF. CONCLUSION: Measuring the preoperative non-tumorous pancreatic ADC may be useful for the prediction of a postoperative PAF.
  • 原因病変の多発が疑われた良性腫瘍性骨軟化症の1例 各種モダリティの中での超音波検査の役割
    曽山 武士, 作原 祐介, 坂本 圭太, 高橋 文也, 阿保 大介, 工藤 與亮, 堀江 達則, 西田 睦
    超音波医学 (公社)日本超音波医学会 42 (1) 92 - 92 1346-1176 2015/01
  • N Fujima, Y Nakamaru, T Sakashita, A Homma, A Tsukahara, K Kudo, H Shirato
    Dento maxillo facial radiology 44 (9) 20150074 - 20150074 0250-832X 2015 [Refereed][Not invited]
     
    OBJECTIVES: To investigate the diagnostic value of tumour blood flow (TBF) obtained with pseudocontinuous arterial spin labelling for the differentiation of squamous cell carcinoma (SCC) and inverted papilloma (IP) in the nasal or sinonasal cavity. METHODS: We retrospectively analysed the cases of 33 patients with SCC and 8 patients with IP in the nasal or sinonasal cavity. Pseudocontinuous arterial spin labelling scanning was performed for all patients using a 3.0-T MR unit. Quantitative TBF values were measured by two neuroradiologists by respectively delineating the whole-tumour regions of interest, and the mean of them was determined as TBF value in each patient. Additionally, the presence of imaging findings of convoluted cerebriform pattern (CCP) on MR T2 weighted images was determined in all patients. As a subgroup analysis, patients with IP were divided into aggressive and non-aggressive IPs depending on their progression range. First, an intraclass correlation coefficient (ICC) of TBF values between two neuroradiologists was determined. Next, a statistical comparison of the TBF value by a Mann-Whitney U test between the patients with SCC and IP was performed. Additionally, the comparison by an ANOVA with a post hoc test of Tukey's method among the SCC, non-aggressive IP and aggressive IP groups was also performed. If significance was observed, the diagnostic accuracy to differentiate SCCs from IPs was calculated. Diagnostic accuracy by CCP findings alone and by the combination of CCP findings and TBF were also assessed. RESULTS: The ICC of TBF values between two neuroradiologists was 0.82. The mean TBF values in the patients with SCC, all patients with IP, those with aggressive IP and those with non-aggressive IP were 141.2 ± 33.1, 77.8 ± 31.5, 109.4 ± 16.7 and 58.8 ± 19.9 ml 100 g⁻¹ min⁻¹, respectively. A significant difference was observed between SCC and IP (p < 0.001), SCC and non-aggressive IP (p < 0.01) and non-aggressive IP and aggressive IP (p < 0.01). The diagnostic accuracy values obtained with receiver operating characteristic curve analysis for the differentiation of SCC from IP and for SCC from non-aggressive IP were 0.90 and 0.92, respectively. The diagnostic accuracy was elevated (0.95 from 0.88) by adding the TBF value to CCP findings. CONCLUSIONS: The pseudocontinuous arterial spin labelling technique can be a useful non-invasive diagnostic tool to differentiate SCC from IP in nasal or sinonasal cavity.
  • Ikuko Uwano, Tsuyoshi Metoki, Fusako Sendai, Ryoko Yoshida, Kohsuke Kudo, Fumio Yamashita, Satomi Higuchi, Kenji Ito, Taisuke Harada, Jonathan Goodwin, Akira Ogawa, Makoto Sasaki
    Magnetic resonance in medical sciences : MRMS : an official journal of Japan Society of Magnetic Resonance in Medicine 14 (1) 35 - 41 1347-3182 2015 [Refereed][Not invited]
     
    PURPOSE: We investigated sensations experienced by a large number of subjects during magnetic resonance (MR) imaging examinations using a 7-tesla scanner and slow table-feed speed. METHODS: After examinations at 7T, 504 of 508 consecutive subjects completed questionnaires using an 11-point scale to rate 14 potential sensations and symptoms during table movement and stationary positioning of the table. We compared scores among the sensations and between table conditions and the mean values of the scores with those reported in previous studies and examined correlations between the scores and subject characteristics. RESULTS: Vertigo and feelings of curving or leaning in the right or left direction during table movement were experienced frequently and markedly compared to other sensations and sensations experienced when the table was stationary (P < 0.01) and were correlated with subject age and examination time (P < 0.05). However, moderate to severe (scores of 5 to 10) vertigo and a curving/leaning feeling during table movement were noted in only 10.5% (vertigo) and 10.9% (curving/leaning) of subjects, and the mean vertigo score, 1.26, appeared to be substantially lower than that reported in a previous study. Reports of a metallic taste, nausea, and light flashes were significantly rarer and weaker than other sensations (P < 0.05). CONCLUSION: Vertigo and feelings of curving during table movement were the most frequent sensations reported during MR imaging examination at 7T. However, the occurrence and severity were low and mild, presumably because of the slow table-feed speed, which suggests that most patients and volunteers found discomfort at 7T acceptable.
  • Jeff Wang, Fumi Kato, Noriko Oyama-Manabe, Ruijiang Li, Yi Cui, Khin Khin Tha, Hiroko Yamashita, Kohsuke Kudo, Hiroki Shirato
    PloS one 10 (11) e0143308  1932-6203 2015 [Refereed][Not invited]
     
    OBJECTIVES: To determine the added discriminative value of detailed quantitative characterization of background parenchymal enhancement in addition to the tumor itself on dynamic contrast-enhanced (DCE) MRI at 3.0 Tesla in identifying "triple-negative" breast cancers. MATERIALS AND METHODS: In this Institutional Review Board-approved retrospective study, DCE-MRI of 84 women presenting 88 invasive carcinomas were evaluated by a radiologist and analyzed using quantitative computer-aided techniques. Each tumor and its surrounding parenchyma were segmented semi-automatically in 3-D. A total of 85 imaging features were extracted from the two regions, including morphologic, densitometric, and statistical texture measures of enhancement. A small subset of optimal features was selected using an efficient sequential forward floating search algorithm. To distinguish triple-negative cancers from other subtypes, we built predictive models based on support vector machines. Their classification performance was assessed with the area under receiver operating characteristic curve (AUC) using cross-validation. RESULTS: Imaging features based on the tumor region achieved an AUC of 0.782 in differentiating triple-negative cancers from others, in line with the current state of the art. When background parenchymal enhancement features were included, the AUC increased significantly to 0.878 (p<0.01). Similar improvements were seen in nearly all subtype classification tasks undertaken. Notably, amongst the most discriminating features for predicting triple-negative cancers were textures of background parenchymal enhancement. CONCLUSIONS: Considering the tumor as well as its surrounding parenchyma on DCE-MRI for radiomic image phenotyping provides useful information for identifying triple-negative breast cancers. Heterogeneity of background parenchymal enhancement, characterized by quantitative texture features on DCE-MRI, adds value to such differentiation models as they are strongly associated with the triple-negative subtype. Prospective validation studies are warranted to confirm these findings and determine potential implications.
  • 脳死肝移植後肝動脈狭窄(HAS)に対しPBA翌日にステント留置を追加し狭窄改善し得た1例
    阿保 大介, 曽山 武士, 作原 祐介, 志村 亮祐, 高橋 文也, 工藤 與亮, 山下 健一郎, 嶋村 剛
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 29 (4) 429 - 429 1340-4520 2014/12
  • 肝仮性動脈瘤を直接穿刺し治療した1例
    高橋 文也, 阿保 大介, 志村 亮祐, 曽山 武士, 作原 祐介, 工藤 與亮, 海老原 裕磨, 田中 栄一, 平野 聡
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 29 (4) 429 - 429 1340-4520 2014/12
  • 子宮体癌再発による外腸骨動脈出血に対しCovered stentにより止血できた1例
    志村 亮祐, 阿保 大介, 曽山 武士, 高橋 文也, 作原 祐介, 工藤 與亮
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 29 (4) 430 - 430 1340-4520 2014/12
  • 内腔.038inchカテーテル対応マイクロバルーンカテーテルを用いた腎血管筋脂肪腫(AML)に対する選択的動脈塞栓術の初期経験
    阿保 大介, 作原 祐介, 曽山 武士, 高橋 文也, 志村 亮祐, 工藤 與亮
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 29 (4) 430 - 431 1340-4520 2014/12
  • 肝内門脈-静脈シャントによる高アンモニア血症に対して塞栓術が著効した1例
    高橋 文也, 作原 祐介, 薮崎 哲史, 阿保 大介, 曽山 武士, 工藤 與亮, 米澤 和彦
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 29 (4) 431 - 431 1340-4520 2014/12
  • Noriyuki Fujima, Daisuke Yoshida, Tomohiro Sakashita, Akihiro Homma, Akiko Tsukahara, Khin Khin Tha, Kohsuke Kudo, Hiroki Shirato
    Magnetic resonance imaging 32 (10) 1206 - 13 0730-725X 2014/12 [Refereed][Not invited]
     
    PURPOSE: To investigate the correlation between perfusion-related parameters obtained with intravoxel incoherent motion (IVIM) and classical perfusion parameters obtained with dynamic contrast-enhanced (DCE) magnetic resonance imaging in patients with head and neck squamous cell carcinoma (HNSCC), and to compare direct and asymptotic fitting, the pixel-by-pixel approach, and a region of interest (ROI)-based approach respectively for IVIM parameter calculation. MATERIALS AND METHODS: Seventeen patients with HNSCC were included in this retrospective study. All magnetic resonance (MR) scanning was performed using a 3T MR unit. Acquisition of IVIM was performed using single-shot spin-echo echo-planar imaging with three orthogonal gradients with 12 b-values (0, 10, 20, 30, 50, 80, 100, 200, 400, 800, 1000, and 2000). Perfusion-related parameters of perfusion fraction 'f' and the pseudo-diffusion coefficient 'D*' were calculated from IVIM data by using least square fitting with the two fitting methods of direct and asymptotic fitting, respectively. DCE perfusion was performed in a total of 64 dynamic phases with a 3.2-s phase interval. The two-compartment exchange model was used for the quantification of tumor blood volume (TBV) and tumor blood flow (TBF). Each tumor was delineated with a polygonal ROI for the calculation of f, f∙D* performed using both the pixel-by-pixel approach and the ROI-based approach. In the pixel-by-pixel approach, after fitting each pixel to obtain f, f∙D* maps, the mean value in the delineated ROI on these maps was calculated. In the ROI-based approach, the mean value of signal intensity was calculated within the ROI for each b-value in IVIM images, and then fitting was performed using these values. Correlations between f in a total of four combinations (direct or asymptotic fitting and pixel-by-pixel or ROI-based approach) and TBV were respectively analyzed using Pearson's correlation coefficients. Correlations between f∙D* and TBF were also similarly analyzed. RESULTS: In all combinations of f and TBV, f∙D* and TBF, there was a significant correlation. In the comparison of f and TBV, a moderate correlation was observed only between f obtained by direct fitting with the pixel-by-pixel approach, whereas a good correlation was observed in the comparisons using the other three combinations. In the comparison of f∙D* and TBF, a good correlation was observed only with f∙D* obtained by asymptotic fitting with the ROI-based approach. In contrast, moderate correlations were observed in the comparisons using the other three combinations. CONCLUSION: IVIM was found to be feasible for the analysis of perfusion-related parameters in patients with HNSCC. Especially, the combination of asymptotic fitting with the ROI-based approach was better correlated with DCE perfusion.
  • 吉田 篤司, 藤間 憲幸, 工藤 與亮
    Medicina (株)医学書院 51 (11) 217 - 224 0025-7699 2014/11
  • Noriyuki Fujima, Kohsuke Kudo, Daisuke Yoshida, Akihiro Homma, Tomohiro Sakashita, Akiko Tsukahara, Khin Khin Tha, Yuri Zaitsu, Satoshi Terae, Hiroki Shirato
    Journal of magnetic resonance imaging : JMRI 40 (4) 920 - 8 1053-1807 2014/10 [Refereed][Not invited]
     
    PURPOSE: To evaluate the feasibility of arterial spin-labeling (ASL) in head and neck cancer for noninvasive measurement of tumor blood flow (TBF), by comparing 1) the TBF change before and after the treatment, and 2) posttreatment TBF and its reduction rate between residual and nonresidual tumors after treatment. MATERIALS AND METHODS: Twenty-two patients with head and neck cancer were evaluated using ASL on 3.0-T magnetic resonance imaging (MRI) before and after nonsurgical treatment. A pulsed ASL sequence with Look–Locker readout was used to calculate quantitative TBF. TBF reduction rates between pre- and posttreatment values were also calculated. Residual tumors were confirmed when present with either histopathologically or clinical follow-up. RESULTS: Pre- and posttreatment mean TBF values were 121.4 ± 27.8 (standard deviation) and 24.9 ± 14.9 mL/100g/min, respectively. Pre- and posttreatment TBF differed significantly. Posttreatment TBF was significantly higher in patients with residual tumors (five patients, 46.9 ± 7.1 mL/100g/min) than in those without (17 patients, 18.4 ± 9.2 mL/100g/min). The TBF reduction rate was significantly lower in patients with residual tumors (0.540.55 ± 0.120.12) than in those without (0.85 ± 0.06). CONCLUSION: ASL allows quantitative assessment of TBF in head and neck cancer. ASL may be useful for noninvasive assessment of tumor viability in head and neck cancer.
  • 原因病変の多発が疑われた良性腫瘍誘発性骨軟化症の1症例(A case of benign tumor-induced osteomalacia that multiple occurrence of the cause lesion was doubted)
    曽山 武士, 作原 祐介, 坂本 圭太, 高橋 文也, 阿保 大介, 工藤 與亮, 一山 芽衣, 渥美 達也, 新井 隆太, 岩崎 倫政
    日本医学放射線学会秋季臨床大会抄録集 50回 S676 - S676 0048-0428 2014/09
  • Fumio Yamashita, Makoto Sasaki, Makoto Saito, Etsuro Mori, Atsushi Kawaguchi, Kohsuke Kudo, Tatsunori Natori, Ikuko Uwano, Kenji Ito, Koichi Saito
    JOURNAL OF NEUROIMAGING 24 (4) 359 - 365 1051-2284 2014/07 [Refereed][Not invited]
     
    OBJECTIVE To determine whether voxel-based morphometry of the cerebrospinal fluid (CSF) space can accurately differentiate iNPH from other related neurological disorders. METHODS Nineteen patients with surgically proven iNPH and 24 patients with Alzheimer's disease (AD), 18 patients with Parkinson's disease (PD), and 14 healthy elderlies were examined. Regions of interest (ROIs) in the ventricular/sylvian (VS) and high convexity/midline (HCM) areas were used in VBM, and differences in CSF volume within these ROIs among the 4 groups were examined. RESULTS The relative CSF volume in the VS-ROI in the iNPH group (.64) was significantly higher than that in the AD, PD, and healthy control groups (.26, .29, and .17, respectively; P < .001), whereas the relative CSF volume in the HCM-ROI was significantly reduced in the iNPH (.10) than in the other (.17, .16, and .16, respectively) groups (P < .001). Furthermore, the ratio of the 2 areas (VS/HCM) was markedly higher in the iNPH (6.87) than in the other (1.65, 1.74, .97, respectively) groups (P < .001), with sensitivity and specificity of .89 and 1.00, respectively. CONCLUSIONS The VBM-based CSF space analysis can detect disproportionate changes in CSF space and differentiate iNPH patients from those with AD or PD and healthy elderlies accurately.
  • Yasuka Kikuchi, Noriko Oyama-Manabe, Masanao Naya, Osamu Manabe, Yuuki Tomiyama, Tsukasa Sasaki, Chietsugu Katoh, Kohsuke Kudo, Nagara Tamaki, Hiroki Shirato
    European radiology 24 (7) 1547 - 56 0938-7994 2014/07 [Refereed][Not invited]
     
    OBJECTIVES: This study introduces a method to calculate myocardium blood flow (MBF) and coronary flow reserve (CFR) using the relatively low-dose dynamic 320-row multi-detector computed tomography (MDCT), validates the method against (15)O-H₂O positron-emission tomography (PET) and assesses the CFRs of coronary artery disease (CAD) patients. METHODS: Thirty-two subjects underwent both dynamic CT perfusion (CTP) and PET perfusion imaging at rest and during pharmacological stress. In 12 normal subjects (pilot group), the calculation method for MBF and CFR was established. In the other 13 normal subjects (validation group), MBF and CFR obtained by dynamic CTP and PET were compared. Finally, the CFRs obtained by dynamic CTP and PET were compared between the validation group and CAD patients (n = 7). RESULTS: Correlation between MBF of MDCT and PET was strong (r = 0.95, P < 0.0001). CFR showed good correlation between dynamic CTP and PET (r = 0.67, P = 0.0126). CFRCT in the CAD group (2.3 ± 0.8) was significantly lower than that in the validation group (5.2 ± 1.8) (P = 0.0011). CONCLUSIONS: We established a method for measuring MBF and CFR with the relatively low-dose dynamic MDCT. Lower CFR was well demonstrated in CAD patients by dynamic CTP. KEY POINTS: • MBF and CFR can be calculated using dynamic CTP with 320-row MDCT. • MBF and CFR showed good correlation between dynamic CTP and PET. • Lower CFR was well demonstrated in CAD patients by dynamic CTP.
  • デジタル/シミュレーターハイブリッドファントムの開発とUS-CT Fusion Imagingのバリデーション
    曽山 武士, 作原 祐介, 阿保 大介, Wang Jeff, 伊藤 陽一, 長谷川 悠, 工藤 與亮, 白土 博樹
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 29 (Suppl.) 200 - 200 1340-4520 2014/05
  • Microballoon catheterを用いたNBCA塞栓術の初期経験 豚動脈を用いた実行可能性の検討
    阿保 大介, 高橋 文也, 曽山 武士, 作原 祐介, 工藤 與亮
    IVR: Interventional Radiology (一社)日本インターベンショナルラジオロジー学会 29 (Suppl.) 253 - 253 1340-4520 2014/05
  • Kenji Ito, Makoto Sasaki, Masakazu Kobayashi, Kuniaki Ogasawara, Takashi Nishihara, Tetsuhiko Takahashi, Tatsunori Natori, Ikuko Uwano, Fumio Yamashita, Kohsuke Kudo
    JOURNAL OF STROKE & CEREBROVASCULAR DISEASES 23 (5) 1019 - 1023 1052-3057 2014/05 [Refereed][Not invited]
     
    Background: Preoperative assessment of intracranial collateral circulation is helpful in predicting cerebral ischemia during surgical procedures for cervical internal carotid artery (ICA) stenosis. However, magnetic resonance angiography (MRA) and other less-invasive techniques cannot evaluate collateral blood flow because these techniques are nonselective. Hence, by using a newly developed selective MRA technique, we attempted to visualize collaterals via the circle of Willis in patients with ICA stenosis. Methods: Twelve patients who underwent carotid endarterectomy were prospectively examined with a 1.5-T MR scanner. Both selective and nonselective MRA were obtained using a 3-dimensional time-of-flight technique, with or without a cylindrical saturation pulse that suppresses the flow signal from the region of the target ICA. Maximum intensity projection MRA images were generated and compared with digital subtraction angiography (DSA) images. Results: In all patients, the distal flow signal of the ipsilateral ICA was completely suppressed on selective MRA compared with nonselective MRA. In addition, collateral blood flow through the anterior and posterior communicating arteries was visualized in 5 and 2 patients, respectively. These findings corresponded well with the DSA imaging. Conclusions: Selective MRA techniques can readily suppress signals from the distal blood flow of the target artery and visualize the presence of collateral flows through the circle of Willis in patients with cervical ICA stenosis.
  • 西田睦, 柴崎晋, 佐藤恵美, 工藤悠輔, 表原里実, 加藤扶美, 工藤與亮, 下國達志, 高橋典彦, 清水力
    超音波医学 (公社)日本超音波医学会 41 (Suppl.) S559 - S559 1346-1176 2014/04/15 [Not refereed][Not invited]
  • F. Kato, R. Mimura, K. Kudo, N. Manabe, T. Fujiwara, H. Sugimori, M. Hosoda, H. Yamashita, H. Shirato
    Japanese Journal of Clinical Radiology 59 (4) 558 - 562 0009-9252 2014/04 [Refereed][Not invited]
     
    We investigated usefulness of the slice selection gradient reversal (SSGR) method in diffusion weighed imaging (DWI) using 3-tesla breast MRI. Thirty-four women with 42 breast tumors were studied. Image quality and lesion detectability were compared between DWI with and without SSGR. DWI with SSGR had higher image quality with little artifact and higher detectability of the lesions than DWI without SSGR. Image quality and lesion detectability were improved on DWI using SSGR.
  • Tatsunori Natori, Makoto Sasaki, Mitsuharu Miyoshi, Hideki Ohba, Noriyuki Katsura, Mao Yamaguchi, Shinsuke Narumi, Hiroyuki Kabasawa, Kohsuke Kudo, Kenji Ito, Yasuo Terayama
    Journal of stroke and cerebrovascular diseases : the official journal of National Stroke Association 23 (4) 706 - 11 1052-3057 2014/04 [Refereed][Not invited]
     
    BACKGROUND: Atherosclerotic lesions in intracranial arteries are a leading cause of ischemic stroke. Magnetic resonance angiography (MRA) is often used to assess atherosclerotic changes by detecting luminal narrowing, whereas it cannot directly visualize atherosclerotic lesions. Here, we used a 3-dimensional vessel wall imaging (3D-VWI) technique to evaluate intracranial arterial wall changes in acute stroke. METHODS: Eighteen consecutive patients with acute noncardioembolic stroke in the middle cerebral artery (MCA) territory who were prospectively examined with a 1.5-T magnetic resonance scanner were studied. T1-weighted (T1-W) 3D-VWI was obtained using a flow-sensitized 3D fast-spin echo technique. Wall thickening of MCA that suggests atherosclerotic plaques was visually evaluated and the contrast ratio (CR) of signal intensity of the lesions to that of the corpus callosum was calculated and compared with stenotic changes by MRA. RESULTS: Wall thickenings of the MCA ipsilateral and contralateral to the lesion were observed in almost all patients on 3D-VWI (94.4% and 94.4%, respectively), whereas MRA showed stenotic changes of 50% only in 1 patient (5.9%; P < .001). The CR of the thickened wall in the ipsilateral MCA was significantly higher than that in the contralateral MCA (median, .53 and .45, respectively; P = .028), suggesting of unstable plaques consisting of hemorrhage or lipid. CONCLUSIONS: The T1-W 3D-VWI can provide direct visualization of atherosclerotic lesions of the intracranial arteries in stroke patients, and it can detect signal change suggestive of unstable plaque.
  • MR灌流画像における脳腫瘍CBV値の悪性度分別能評価 解析ソフトウェア間の比較(第3報)
    上野 育子, 工藤 與亮, 佐々木 真理, 山下 典生, Goodwin Jonathan, 平井 俊範, 藤間 憲幸
    Japanese Journal of Radiology (公社)日本医学放射線学会 32 (Suppl.) 8 - 8 1867-1071 2014/02
  • Takaaki Beppu, Kazunori Terasaki, Toshiaki Sasaki, Shunrou Fujiwara, Hideki Matsuura, Kuniaki Ogasawara, Koichiro Sera, Noriyuki Yamada, Noriyuki Uesugi, Tamotsu Sugai, Kohsuke Kudo, Makoto Sasaki, Shigeru Ehara, Ren Iwata, Yoshihiro Takai
    Molecular imaging and biology 16 (1) 127 - 35 1536-1632 2014/02 [Refereed][Not invited]
     
    PURPOSE: The aim of this study was to clarify the reliability of positron emission tomography (PET) using a new hypoxic cell tracer, 1-(2-[(18)F]fluoro-1-[hydroxymethyl]ethoxy)methyl-2-nitroimidazole ((18)F-FRP170). PROCEDURES: Twelve patients with glioblastoma underwent (18)F-FRP170 PET before tumor resection. Mean standardized uptake value (SUV) and normalized SUV were calculated at regions within a tumor showing high (high-uptake area) and relatively low (low-uptake area) accumulations of (18)F-FRP170. In these areas, intratumoral oxygen pressure (tpO2) was measured using microelectrodes during tumor resection. RESULTS: Mean tpO2 was significantly lower in the high-uptake area than in the low-uptake area. A significant negative correlation was evident between normalized SUV and tpO2 in the high-uptake area. CONCLUSION: The present findings suggest that high accumulation on (18)F-FRP170 PET represents viable hypoxic tissues in glioblastoma.
  • Ikuko Uwano, Kohsuke Kudo, Fumio Yamashita, Jonathan Goodwin, Satomi Higuchi, Kenji Ito, Taisuke Harada, Akira Ogawa, Makoto Sasaki
    Medical physics 41 (2) 022302 - 022302 0094-2405 2014/02 [Refereed][Not invited]
     
    PURPOSE: To evaluate the performance and efficacy for intensity inhomogeneity correction of various sequences of the human brain in 7T MRI using the extended version of the unified segmentation algorithm. MATERIALS: Ten healthy volunteers were scanned with four different sequences (2D spin echo [SE], 3D fast SE, 2D fast spoiled gradient echo, and 3D time-of-flight) by using a 7T MRI system. Intensity inhomogeneity correction was performed using the "New Segment" module in SPM8 with four different values (120, 90, 60, and 30 mm) of full width at half maximum (FWHM) in Gaussian smoothness. The uniformity in signals in the entire white matter was evaluated using the coefficient of variation (CV); mean signal intensities between the subcortical and deep white matter were compared, and contrast between subcortical white matter and gray matter was measured. The length of the lenticulostriate (LSA) was measured on maximum intensity projection (MIP) images in the original and corrected images. RESULTS: In all sequences, the CV decreased as the FWHM value decreased. The differences of mean signal intensities between subcortical and deep white matter also decreased with smaller FWHM values. The contrast between white and gray matter was maintained at all FWHM values. LSA length was significantly greater in corrected MIP than in the original MIP images. CONCLUSIONS: Intensity inhomogeneity in 7T MRI can be successfully corrected using SPM8 for various scan sequences.
  • Jeff Wang, Fumi Kato, Kohsuke Kudo, Hiroko Yamashita, Hiroki Shirato
    Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) 8539 334 - 340 1611-3349 2014 [Refereed][Not invited]
     
    Early classification of breast cancers by molecular subtype allows for expeditious characterization of the disease and selection of appropriate treatment options. This ability is especially a concern for "triple- negative" cancers, which lack expression of the three cell surface receptors that most breast cancer hormonal therapies target, tend to be the most aggressive/metastatic compared to other subtypes, have lymph node involvement at diagnoses, and have relatively poor prognoses. In this study, we aim to develop predictive models using Dynamic Contrast-Enhanced (DCE) MRI-extracted features to identify triple-negative cancers and axillary lymph node metastasis at the time of diagnostic imaging. Using only morphological, pharmacokinetic, densitometric, statistical, textural, and textural kinetic features obtained from DCE-MRI, we were able to classify 91.3% of 69 lesions correctly for triple-negative status with a sensitivity of 55.6%, a specificity of 96.7, and an AUC of 0.889 71.6% of lesions correctly for lymph node metastasis with a sensitivity of 50.0%, a specificity of 82.2%, and an AUC of 0.677. © 2014 Springer International Publishing.
  • Gen Haba, Hidekazu Nishigori, Makoto Sasaki, Koujiro Tohyama, Kohsuke Kudo, Yutaka Matsumura, Toru Sugiyama, Keisuke Kagami, Yu Tezuka, Atsushi Sanbe, Hideo Nishigori
    Psychopharmacology 231 (1) 221 - 30 0033-3158 2014/01 [Refereed][Not invited]
     
    RATIONALE AND OBJECTIVES: The effects of low thyroid hormone level during embryogenesis on MRI of the brain and social behaviors of hatchlings were examined using "fertilized hen's egg-embryo-chick" system. METHODS AND RESULTS: Control and hatchlings treated with methimazole (20 μmol/egg), which hatched 3 days later than controls were examined. The results are as follows: 1. The MRI examination of the midsagittal section of the brain on hatch day showed that the sizes, by T1- and ADC values by diffusion-weighted images, of the optic lobe and cerebellum of the MMI-hatchlings were significantly bigger than those of the controls. 2. The social behaviors on post-hatch day 3 were based on the following tests: (a) Aggregation test: The speed of four chicks, individually isolated by cardboard barriers in a box, to make a group upon the removal of barriers. (b) Belongingness tests: The speed of a chick isolated at a corner to join the group of three chicks placed at the opposite corner. (c) Vocalization test: The number of decibel produced by a chick isolated at a corner using a sound meter. These tests demonstrated that MMI-hatchlings took longer times and had weaker vocalization than the controls, significantly. 3. Upregulation of THRβ mRNA after MMI treatment suggested that THR was necessary for cerebellum development. CONCLUSIONS: The MMI exposure during the last week of embryogenesis possibly delayed the myelination of certain brain regions and impaired the social behaviors of hatchlings. The chick embryos can be easily induced with hypothyroidism without maternal influences, and the hatchling's behaviors were analyzed using a video camera. The present method will be useful for assessing the effects of unfavorable influences during embryogenesis on social behaviors in later life.
  • Kohsuke Kudo, Timothé Boutelier, Fabrice Pautot, Kaneyoshi Honjo, Jin-Qing Hu, Hai-Bin Wang, Katsuya Shintaku, Ikuko Uwano, Makoto Sasaki
    Magnetic resonance in medical sciences : MRMS : an official journal of Japan Society of Magnetic Resonance in Medicine 13 (1) 45 - 50 1347-3182 2014 [Refereed][Not invited]
     
    PURPOSE: We compared the performances of a Bayesian estimation method and oscillation index singular value decomposition (oSVD) deconvolution for predicting final infarction using data previously obtained from 10 cynomolgus monkeys with permanent unilateral middle cerebral artery (MCA) occlusion. METHODS: We conducted baseline perfusion-weighted imaging 3 hours after MCA occlusion and generated time to peak, first moment of transit, cerebral blood flow, cerebral blood volume, and mean transit time maps using Bayesian and oSVD methods. Final infarct volume was determined by follow-up diffusion-weighted imaging (DWI) scanned 47 hours after MCA occlusion and from histological specimens. We used a region growing technique with various thresholds to determine perfusion abnormality volume. The best threshold was defined when the mean perfusion volume matched the mean final infarct volume, and Pearson's correlation coefficients (r) and intraclass correlations (ICC) were calculated between perfusion abnormality and final infarct volume at that threshold. These coefficients were compared between Bayesian and oSVD using Wilcoxon's signed rank test. P-value < 0.05 was considered a statistically significant difference. RESULTS: The Pearson's correlation coefficients were larger but not significantly different for the Bayesian technique than oSVD in 4 of 5 perfusion maps when final infarct was determined by specimen volume (P = 0.104). When final infarct volume was defined by DWI volume, all perfusion maps had a significantly higher correlation coefficient by Bayesian technique than oSVD (P = 0.043). For ICC, all perfusion maps had higher value in Bayesian than oSVD calculation, and significant differences were observed both on specimen- and DWI-defined volumes (P = 0.043 for both). CONCLUSION: The Bayesian method is more reliable than oSVD deconvolution in estimating final infarct volume.
  • Makoto Sasaki, Kohsuke Kudo, Soren Christensen, Fumio Yamashita, Jonathan Goodwin, Satomi Higuchi, Akira Ogawa
    Journal of stroke and cerebrovascular diseases : the official journal of National Stroke Association 22 (8) 1212 - 5 1052-3057 2013/11 [Refereed][Not invited]
     
    Perfusion computed tomography and perfusion-weighted magnetic resonance imaging are used to evaluate the extent of the area with ischemic penumbra; however, different parameters, algorithms, and software packages show significant discrepancies in the size of perfusion abnormalities, which should be minimized. Recently, cross-validation studies were performed using digital phantoms and have elucidated the precision and reliability of various penumbral imaging techniques. These research initiatives can promote further multicenter trials on recanalization therapies by providing accurate inclusion/exclusion criteria for appropriate patient selection.
  • Yuiko Sato, Kenji Ito, Kuniaki Ogasawara, Makoto Sasaki, Kohsuke Kudo, Toshiyuki Murakami, Takamasa Nanba, Hideaki Nishimoto, Kenji Yoshida, Masakazu Kobayashi, Yoshitaka Kubo, Tomohiko Mase, Akira Ogawa
    Neurosurgery 73 (4) 592 - 8 0148-396X 2013/10 [Refereed][Not invited]
     
    BACKGROUND: Carotid endarterectomy (CEA) might improve cognitive function. Fractional anisotropy (FA) values in the cerebral white matter derived from diffusion tensor magnetic resonance imaging (DTI) correlate with cognitive function in patients with various central nervous system diseases. OBJECTIVE: To use tract-based spatial statistics to determine whether postoperative changes of FA values in the cerebral white matter derived from DTI are associated with cognitive improvement after uncomplicated CEA. METHODS: In 80 patients undergoing CEA for ipsilateral internal carotid artery stenosis (≥70%), FA values in the cerebral white matter were derived from DTI before and 1 month after surgery and were analyzed by using tract-based spatial statistics. Neuropsychological testing, consisting of the Wechsler Adult Intelligence Scale Revised, the Wechsler Memory Scale and the Rey-Osterreith Complex Figure test, was also performed preoperatively and after the first postoperative month. RESULTS: Based on the neuropsychological assessments, 11 (14%) patients were defined as having postoperatively improved cognition. The difference between the 2 mean FA values (postoperative values minus preoperative values) in the cerebral hemisphere ipsilateral to surgery was significantly associated with postoperative cognitive improvement (95% confidence intervals, 2.632-9.877; P = .008). White matter FA values in patients with postoperative cognitive improvement were significantly increased after surgery in the whole ipsilateral cerebral hemisphere, in the contralateral anterior cerebral artery territory, and in the watershed zone between the contralateral anterior and middle cerebral arteries. CONCLUSION: Postoperative increase in cerebral white matter FA on DTI is associated with cognitive improvement after uncomplicated CEA.
  • Makoto Sasaki, Kohsuke Kudo, Timothé Boutelier, Fabrice Pautot, Soren Christensen, Ikuko Uwano, Jonathan Goodwin, Satomi Higuchi, Kenji Ito, Fumio Yamashita
    Neuroradiology 55 (10) 1197 - 203 0028-3940 2013/10 [Refereed][Not invited]
     
    INTRODUCTION: A new deconvolution algorithm, the Bayesian estimation algorithm, was reported to improve the precision of parametric maps created using perfusion computed tomography. However, it remains unclear whether quantitative values generated by this method are more accurate than those generated using optimized deconvolution algorithms of other software packages. Hence, we compared the accuracy of the Bayesian and deconvolution algorithms by using a digital phantom. METHODS: The digital phantom data, in which concentration-time curves reflecting various known values for cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT), and tracer delays were embedded, were analyzed using the Bayesian estimation algorithm as well as delay-insensitive singular value decomposition (SVD) algorithms of two software packages that were the best benchmarks in a previous cross-validation study. Correlation and agreement of quantitative values of these algorithms with true values were examined. RESULTS: CBF, CBV, and MTT values estimated by all the algorithms showed strong correlations with the true values (r = 0.91-0.92, 0.97-0.99, and 0.91-0.96, respectively). In addition, the values generated by the Bayesian estimation algorithm for all of these parameters showed good agreement with the true values [intraclass correlation coefficient (ICC) = 0.90, 0.99, and 0.96, respectively], while MTT values from the SVD algorithms were suboptimal (ICC = 0.81-0.82). CONCLUSIONS: Quantitative analysis using a digital phantom revealed that the Bayesian estimation algorithm yielded CBF, CBV, and MTT maps strongly correlated with the true values and MTT maps with better agreement than those produced by delay-insensitive SVD algorithms.
  • Max Wintermark, Gregory W Albers, Joseph P Broderick, Andrew M Demchuk, Jochen B Fiebach, Jens Fiehler, James C Grotta, Gary Houser, Tudor G Jovin, Kennedy R Lees, Michael H Lev, David S Liebeskind, Marie Luby, Keith W Muir, Mark W Parsons, Rüdiger von Kummer, Joanna M Wardlaw, Ona Wu, Albert J Yoo, Andrei V Alexandrov, Jeffry R Alger, Richard I Aviv, Roland Bammer, Jean-Claude Baron, Fernando Calamante, Bruce C V Campbell, Trevor C Carpenter, Søren Christensen, William A Copen, Colin P Derdeyn, E Clarke Haley Jr, Pooja Khatri, Kohsuke Kudo, Maarten G Lansberg, Lawrence L Latour, Ting-Yim Lee, Richard Leigh, Weili Lin, Patrick Lyden, Grant Mair, Bijoy K Menon, Patrik Michel, Robert Mikulik, Raul G Nogueira, Leif Ostergaard, Salvador Pedraza, Christian H Riedel, Howard A Rowley, Pina C Sanelli, Makoto Sasaki, Jeffrey L Saver, Pamela W Schaefer, Peter D Schellinger, Georgios Tsivgoulis, Lawrence R Wechsler, Philip M White, Greg Zaharchuk, Osama O Zaidat, Stephen M Davis, Geoffrey A Donnan, Anthony J Furlan, Werner Hacke, Dong-Wha Kang, Chelsea Kidwell, Vincent N Thijs, Götz Thomalla, Steven J Warach
    Stroke 44 (9) 2628 - 39 0039-2499 2013/09 [Refereed][Not invited]
  • Max Wintermark, Jens Fiehler, Kohsuke Kudo, David S. Liebeskind, Marie Luby, Patrik Michel, Raul Nogueira, Mark Parsons, Makoto Sasaki, Joanna Wardlaw, Ona Wu, Weiwei Zhang, Guangming Zhu, Steven Warach
    Stroke 44 (8) 2091  0039-2499 2013/08 [Refereed][Not invited]
  • Kimihiro Ogisu, Kohsuke Kudo, Makoto Sasaki, Ken Sakushima, Ichiro Yabe, Hidenao Sasaki, Satoshi Terae, Mitsuhiro Nakanishi, Hiroki Shirato
    Neuroradiology 55 (6) 719 - 24 0028-3940 2013/06 [Refereed][Not invited]
     
    INTRODUCTION: Neuromelanin-sensitive MRI has been reported to be used in the diagnosis of Parkinson's disease (PD), which results from loss of dopamine-producing cells in the substantia nigra pars compacta (SNc). In this study, we aimed to apply a 3D turbo field echo (TFE) sequence for neuromelanin-sensitive MRI and to evaluate the diagnostic performance of semi-automated method for measurement of SNc volume in patients with PD. METHODS: We examined 18 PD patients and 27 healthy volunteers (control subjects). A 3D TFE technique with off-resonance magnetization transfer pulse was used for neuromelanin-sensitive MRI on a 3T scanner. The SNc volume was semi-automatically measured using a region-growing technique at various thresholds (ranging from 1.66 to 2.48), with the signals measured relative to that for the superior cerebellar peduncle. Receiver operating characteristic (ROC) analysis was performed at all thresholds. Intra-rater reproducibility was evaluated by intraclass correlation coefficient (ICC). RESULTS: The average SNc volume in the PD group was significantly smaller than that in the control group at all the thresholds (P < 0.01, student t test). At higher thresholds (>2.0), the area under the curve of ROC (Az) increased (0.88). In addition, we observed balanced sensitivity and specificity (0.83 and 0.85, respectively). At lower thresholds, sensitivity tended to increase but specificity reduced in comparison with that at higher thresholds. ICC was larger than 0.9 when the threshold was over 1.86. CONCLUSIONS: Our method can distinguish the PD group from the control group with high sensitivity and specificity, especially for early stage of PD.
  • Chigumi Ohtsuka, Makoto Sasaki, Kanako Konno, Mizuho Koide, Kanako Kato, Junko Takahashi, Satoshi Takahashi, Kohsuke Kudo, Fumio Yamashita, Yasuo Terayama
    Neuroscience letters 541 93 - 8 0304-3940 2013/04/29 [Refereed][Not invited]
     
    Neuromelanin-sensitive magnetic resonance imaging is able to visualize changes associated with neuronal loss in the substantia nigra pars compacta (SNc) and locus coeruleus (LC) in patients with Parkinson's disease (PD). However, the diagnostic accuracy of this technique in the early stages of PD remains unknown. Therefore, changes in the SNc and LC observed using neuromelanin imaging were evaluated in patients with early PD. The signal intensities of the lateral, central, and medial parts of the SNc and that of the LC were measured, and the contrast ratios (CRs) were calculated against the adjacent white matter structures. CRs in the lateral part of the SNc and in the LC were significantly reduced in the early PD group when compared with the controls. Sensitivities and specificities in discriminating early PD patients from healthy controls were 73% and 87% in lateral SNc and 82% and 90% in LC, respectively. Neuromelanin imaging can depict signal alterations in the lateral part of the SNc and in the LC in patients with PD, even in its early stage, and can discriminate between these patients and healthy individuals with high sensitivities and specificities.
  • Ikuko Uwano, Makoto Sasaki, Kohsuke Kudo, Shunrou Fujiwara, Mao Yamaguchi, Ayumi Saito, Kuniaki Ogasawara, Akira Ogawa
    Journal of neuroimaging : official journal of the American Society of Neuroimaging 23 (2) 197 - 201 1051-2284 2013/04 [Refereed][Not invited]
     
    BACKGROUND AND PURPOSE: Diffusion anisotropy color-coded maps of cerebral white matter can be generated from orthogonal anisotropic diffusion-weighted imaging (DWI) using the three-dimensional anisotropy contrast (3DAC) technique, but its precision has not been fully validated. Hence, we attempted to determine whether 3DAC is comparable to a diffusion tensor imaging (DTI) color map. METHODS: We examined 15 healthy individuals and generated color-coded maps using 3DAC as well as using primary eigenvector (e1) and fractional anisotropy (FA) from identical DTI datasets. The difference in the direction of the 3DAC vector from e1 (θ) in cerebral white matter was evaluated. Correlations between θ and FA or obliqueness of e1 were also examined. RESULTS: In cerebral white matter, θ had significantly negative and positive correlations with FA values and e1 obliqueness, respectively. Among white matter tracts, the pyramidal tract, cingulum, and corpus callosum, which had significantly high FA and/or low obliqueness, exhibited similar coloration and significantly smaller θ (4.4° ± 1.6°, 9.3° ± 2.8°, and 11.2° ± 1.1°, respectively) than the entire white matter (13.9° ± 1.1°). CONCLUSIONS: The 3DAC could visualize directional information of white matter tracts as precisely DTI-based color maps did, particularly when FA was large and/or e1 directions were orthogonal.
  • Kohsuke Kudo, Soren Christensen, Makoto Sasaki, Leif Østergaard, Hiroki Shirato, Kuniaki Ogasawara, Max Wintermark, Steven Warach
    Radiology 267 (1) 201 - 11 0033-8419 2013/04 [Refereed][Not invited]
     
    PURPOSE: To design a digital phantom data set for computed tomography (CT) perfusion and perfusion-weighted imaging on the basis of the widely accepted tracer kinetic theory in which the true values of cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT), and tracer arrival delay are known and to evaluate the accuracy and reliability of postprocessing programs using this digital phantom. MATERIALS AND METHODS: A phantom data set was created by generating concentration-time curves reflecting true values for CBF (2.5-87.5 mL/100 g per minute), CBV (1.0-5.0 mL/100 g), MTT (3.4-24 seconds), and tracer delays (0-3.0 seconds). These curves were embedded in human brain images. The data were analyzed by using 13 algorithms each for CT and magnetic resonance (MR), including five commercial vendors and five academic programs. Accuracy was assessed by using the Pearson correlation coefficient (r) for true values. Delay-, MTT-, or CBV-dependent errors and correlations between time to maximum of residue function (Tmax) were also evaluated. RESULTS: In CT, CBV was generally well reproduced (r > 0.9 in 12 algorithms), but not CBF and MTT (r > 0.9 in seven and four algorithms, respectively). In MR, good correlation (r > 0.9) was observed in one-half of commercial programs, while all academic algorithms showed good correlations for all parameters. Most algorithms had delay-dependent errors, especially for commercial software, as well as CBV dependency for CBF or MTT calculation and MTT dependency for CBV calculation. Correlation was good in Tmax except for one algorithm. CONCLUSION: The digital phantom readily evaluated the accuracy and characteristics of the CT and MR perfusion analysis software. All commercial programs had delay-induced errors and/or insufficient correlations with true values, while academic programs for MR showed good correlations with true values. SUPPLEMENTAL MATERIAL: http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.12112618/-/DC1.
  • 脳腫瘍におけるMR灌流画像のCBV評価 解析ソフトウェア間の比較
    上野 育子, 工藤 與亮, 佐々木 真理, 阿久津 仁美, 齊藤 絵里奈, 千葉 映奈, 平井 俊範, 藤間 憲幸, 江原 茂
    Japanese Journal of Radiology (公社)日本医学放射線学会 31 (Suppl.I) 5 - 5 1867-1071 2013/02
  • MR灌流画像における脳腫瘍悪性度別のCBV評価 解析ソフトウェア間の比較(第2報)
    上野 育子, 工藤 與亮, 佐々木 真理, 阿久津 仁美, 齊藤 絵里奈, 千葉 映奈, 平井 俊範, 藤間 憲幸
    Japanese Journal of Radiology (公社)日本医学放射線学会 31 (Suppl.I) 13 - 13 1867-1071 2013/02
  • Noriko Oyama-Manabe, Takahiro Sato, Ichizo Tsujino, Kohsuke Kudo, Osamu Manabe, Fumi Kato, Nael F Osman, Satoshi Terae
    The international journal of cardiovascular imaging 29 (2) 371 - 8 1569-5794 2013/02 [Refereed][Not invited]
     
    The aim of this study was to explore whether the regional peak longitudinal (LS) and circumferential strains (CS) at the right ventricular (RV) free wall could be used to identify global RV dysfunction in relation to RV ejection fraction (RVEF) and plasma concentration of brain natriuretic peptide (BNP) in pulmonary hypertension (PH). A total of 37 consecutive patients diagnosed with PH and 13 healthy control subjects were included. Fast strain encoded and routine cine MRI was performed. The LS and CS at three RV levels were quantified and their relations with RVEF and BNP were investigated. Receiver operating characteristic (ROC) analysis was employed to assess the diagnostic utility of strain encoded MRI for the detection of low RVEF. Significant correlations with LS were observed for RVEF and BNP. Compared to CS, LS showed better correlation with RVEF. The mid-ventricular level of RV was the most sensitive site for evaluation of RV dysfunction. According to our ROC analysis, LS showed higher sensitivity and specificity to detect low RVEF. Compared to CS, LS showed stronger correlations with RVEF and BNP and could be a good detector of RV dysfunction in PH.
  • Makoto Sasaki, Fumio Yamashita, Kohsuke Kudo
    Current Clinical Neurology 44 159 - 164 1559-0585 2013 [Refereed][Not invited]
     
    Neuromelanin, a black pigment present in dopaminergic and noradrenergic neurons in the substantia nigra pars compacta (SNc) and locus ceruleus (LC), has paramagnetic T1-shortening effects. Conventional magnetic resonance imaging (cMRI) techniques fail to depict the contrast generated by neuromelanin, but there are some neuromelanin-sensitive techniques that allow direct visualization of the SNc and LC as evident high-signal areas. In Parkinson disease, neuromelanin-related signals from the SNc and LC are attenuated suggesting neuronal loss in both these nuclei. In other neurodegenerative and psychiatric disorders, signal alterations of SNc and/or LC can also be shown. Neuromelanin-sensitive MRI is a promising technique to assess changes in these nuclei that occur in Parkinson disease and other related disorders.
  • S. Narumi, M. Sasaki, H. Ohba, K. Ogasawara, M. Kobayashi, J. Hitomi, K. Mori, K. Ohura, M. Yamaguchi, K. Kudo, Y. Terayama
    AMERICAN JOURNAL OF NEURORADIOLOGY 34 (1) 191 - 197 0195-6108 2013/01 [Refereed][Not invited]
     
    BACKGROUND AND PURPOSE: Electrocardiographic gating, commonly used in MR carotid plaque imaging, can negatively affect intraplaque contrast if the TR is inappropriate. The present study aimed to determine whether a non-gated technique with appropriate TRs can accurately evaluate intraplaque characteristics in specimens excised by CEA. MATERIALS AND METHODS: We prospectively examined 40 consecutive patients who underwent CEA (59-82 years of age) by using a 1.5T scanner. Axial T1WI with a TR of 500 ms and PDWI and T2WI with a TR of 3000 ms with a self-navigated rotating-blade scan instead of cardiac gating were obtained. Signal intensities of the plaque and adjacent muscle were measured, and the CR on T1WI, PDWI, and T2WI as well as the gray-scale median on US were correlated with the pathologic findings of the CEA specimens. RESULTS: On T1WI, the CRs of the carotid plaques differed significantly among groups in which the main components were histologically confirmed as fibrous tissue, lipid/necrosis, and hemorrhage (0.54-1.17,1.16-1.53, and 1.40-2.29, respectively). The sensitivity and specificity for discriminating lipid/necrosis/hemorrhage from fibrous tissue were 96% and 100%, respectively. On T2WI, the CRs of plaques with lipid/necrosis were significantly higher than those of other groups, but the CRs on PDWI and the gray-scale median on US were not significantly different among the groups. CONCLUSIONS: Non-gated MR plaque imaging, particularly T1WI, can readily predict the intraplaque main components of the carotid artery with high sensitivity and specificity.
  • Ayumi Saito, Makoto Sasaki, Kuniaki Ogasawara, Masakazu Kobayashi, Jiro Hitomi, Shinsuke Narumi, Hideki Ohba, Mao Yamaguchi, Kohsuke Kudo, Yasuo Terayama
    Neuroradiology 54 (11) 1187 - 94 0028-3940 2012/11 [Refereed][Not invited]
     
    INTRODUCTION: Several magnetic resonance (MR) imaging techniques are used to examine atherosclerotic plaque of carotid arteries; however, the best technique for visualizing intraplaque characteristics has yet to be determined. Here, we directly compared four kinds of T1-weighted (T1W) imaging techniques with pathological findings in patients with carotid stenosis. METHODS: A total of 31 patients who were candidates for carotid endarterectomy were prospectively examined using a 1.5-T MRI scanner, which produced four kinds of T1W images, including non-gated spin echo (SE), cardiac-gated black-blood (BB) fast-SE (FSE), magnetization-prepared rapid acquisition with gradient echo (MPRAGE), and source image of three-dimensional time-of-flight MR angiography (SI-MRA). The signal intensity of the carotid plaque was manually measured, and the contrast ratio (CR) against the adjacent muscle was calculated. CRs from the four imaging techniques were compared to each other and correlated with histopathological specimens. RESULTS: CRs of the carotid plaques mainly containing fibrous tissue, lipid/necrosis, and hemorrhage were significantly different with little overlaps (range: 0.92-1.15, 1.22-1.52, and 1.55-2.30, respectively) on non-gated SE. However, BB-FSE showed remarkable overlaps among the three groups (0.89-1.10, 1.07-1.23, and 1.01-1.42, respectively). MPRAGE could discriminate fibrous plaques from hemorrhagic plaques but not from lipid/necrosis-rich plaques: (0.77-1.07, 1.45-2.43, and 0.85-1.42, respectively). SI-MRA showed the same tendencies (1.01-1.39, 1.45-2.57, and 1.12-1.39, respectively). CONCLUSION: Among T1W MR imaging techniques, non-gated SE images can more accurately characterize intraplaque components in patients who underwent CEA when compared with cardiac-gated BB-FSE, MPRAGE, and SI-MRA images.
  • Mao Yamaguchi, Makoto Sasaki, Hideki Ohba, Kiyofumi Mori, Shinsuke Narumi, Noriyuki Katsura, Kazumasa Ohura, Kohsuke Kudo, Yasuo Terayama
    Neuroradiology 54 (9) 939 - 45 0028-3940 2012/09 [Refereed][Not invited]
     
    INTRODUCTION: Cilostazol, an antiplatelet agent, is reported to induce the regression of atherosclerotic changes. However, its effects on carotid plaques are unknown. Hence, we quantitatively investigated the changes that occur within carotid plaques during cilostazol administration using three-dimensional (3D) ultrasonography (US) and non-gated magnetic resonance (MR) plaque imaging. METHODS: We prospectively examined 16 consecutive patients with carotid stenosis. 3D-US and T1-weighted MR plaque imaging were performed at baseline and 6 months after initiating cilostazol therapy (200 mg/day). We measured the volume and grayscale median (GSM) of the plaques from 3D-US data. We also calculated the contrast ratio (CR) of the carotid plaque against the adjacent muscle and areas of the intraplaque components: fibrous tissue, lipid, and hemorrhage components. RESULTS: The plaque volume on US decreased significantly (median at baseline and 6 months, 0.23 and 0.21 cm(3), respectively; p = 0.03). In the group exhibiting a plaque volume reduction of more than 10%, GSM on US increased significantly (24.8 and 71.5, respectively; p = 0.04) and CR on MRI decreased significantly (1.13 and 1.04, respectively; p = 0.02). In this group, in addition, the percent area of the fibrous component on MRI increased significantly (68.6% and 79.4%, respectively; p = 0.02), while those of the lipid and hemorrhagic components decreased (24.9% and 20.5%, respectively; p = 0.12) (1.0% and 0.0%, respectively; p = 0.04). There were no substantial changes in intraplaque characteristics in either US or MRI in the other group. CONCLUSIONS: 3D-US and MR plaque imaging can quantitatively detect changes in the size and composition of carotid plaques during cilostazol therapy.
  • Carlos Leiva-Salinas, James M Provenzale, Kohsuke Kudo, Makoto Sasaki, Max Wintermark
    Neuroradiology 54 (9) 907 - 18 0028-3940 2012/09 [Refereed][Not invited]
     
    The five questions answered in this article revolve around the different parameters resulting from perfusion imaging processing, and this clarifies the frequently confusing terminology used to describe these parameters. More specifically, the article discusses the different imaging techniques and main mathematical models behind perfusion imaging, reviews the perfusion attributes of brain tissue, and proposes a standardized parameter terminology to facilitate understanding and avoid common misinterpretations.
  • Makoto Sasaki, Kohsuke Kudo, Ikuko Uwano, Hiroyuki Kabasawa, Tsuyoshi Matsuda
    Brain and nerve = Shinkei kenkyu no shinpo 64 (9) 1057 - 62 1881-6096 2012/09 [Refereed][Not invited]
     
    The introduction of ultrahigh-field MRI at 7 tesla (7T) has increased the interest in the use of neuroimaging techniques in clinical research. The high signal-to-noise ratio and profound susceptibility effect at 7T can remarkably improve the spatial resolution and image contrast of structural imaging, susceptibility imaging, and functional imaging techniques, whereas the heating effects of the radio frequency and the inhomogeneities of the local magnetic field can have substantial negative effects on parameter setting, acquisition time, and image quality. T1 prolongation at 7T can improve the enhancement effects of gadolinium agents and the inflow effects on MR angiography and arterial spin labeling. Ultrahigh-field MRI is expected to have a high clinical impact in the near future; however, further technological advances tailored to ultrahigh-field systems as well as the accumulation of scientific evidence will be needed to establish its clinical significance.
  • 藤間 憲幸, 工藤 與亮
    INNERVISION (株)インナービジョン 27 (9) 44 - 47 0913-8919 2012/08 
    血液灌流は脳実質の機能的な情報を含む重要な評価項目の1つであり、多岐にわたる脳疾患でその有用性が示されている。MRIを用いた灌流画像は、造影剤を用いて施行するdynamic susceptibility contrast(DSC)法と、血液を内因性のトレーサーとして使用するarterial spin labeling(ASL)法の2つに大別される。従来、灌流画像の取得は、DSC法がその大部分を占めていたが、3T MRIの普及とともにASL法の使用頻度が大きく増加している。DSC法とASL法にはそれぞれの長所と短所があり、例えばDSC法はガドリニウム(Gd)造影剤を用いるため侵襲的であるが、ASLは完全に非侵襲的であり、繰り返し撮像することも可能である。しかし、DSC法と比べてASL法は原理的にSNRが非常に低く、特に遅延血流の評価は困難な場合が多い。実臨床では、DSC法、ASL法それぞれの原理や特性を理解して、疾患ごとに使い分ける必要がある。本稿では、DSC法とASL法それぞれの原理的な解説、画像取得における工夫や脳疾患における使い分けについて概説する。(著者抄録)
  • Timothé Boutelier, Koshuke Kudo, Fabrice Pautot, Makoto Sasaki
    IEEE transactions on medical imaging 31 (7) 1381 - 95 2012/07 [Refereed][Not invited]
     
    A delay-insensitive probabilistic method for estimating hemodynamic parameters, delays, theoretical residue functions, and concentration time curves by computed tomography (CT) and magnetic resonance (MR) perfusion weighted imaging is presented. Only a mild stationarity hypothesis is made beyond the standard perfusion model. New microvascular parameters with simple hemodynamic interpretation are naturally introduced. Simulations on standard digital phantoms show that the method outperforms the oscillating singular value decomposition (oSVD) method in terms of goodness-of-fit, linearity, statistical and systematic errors on all parameters, especially at low signal-to-noise ratios (SNRs). Delay is always estimated sharply with user-supplied resolution and is purely arterial, by contrast to oSVD time-to-maximum TMAX that is very noisy and biased by mean transit time (MTT), blood volume, and SNR. Residue functions and signals estimates do not suffer overfitting anymore. One CT acute stroke case confirms simulation results and highlights the ability of the method to reliably estimate MTT when SNR is low. Delays look promising for delineating the arterial occlusion territory and collateral circulation.
  • Shunrou Fujiwara, Takaaki Beppu, Hideaki Nishimoto, Katsumi Sanjo, Atsuhiko Koeda, Kiyoshi Mori, Kohsuke Kudo, Makoto Sasaki, Kuniaki Ogasawara
    Neuroradiology 54 (7) 681 - 9 0028-3940 2012/07 [Refereed][Not invited]
     
    INTRODUCTION: The present study aimed to detect the main regions of cerebral white matter (CWM) showing damage in the subacute phase for CO-poisoned patients with chronic neurological symptoms using voxel-based analysis (VBA) with diffusion tensor imaging (DTI). METHODS: Subjects comprised 22 adult CO-poisoned patients and 16 age-matched healthy volunteers as controls. Patients were classified into patients with transient acute symptoms only (group A) and patients with chronic neurological symptoms (group S). In all patients, DTI covering the whole brain was performed with a 3.0-T magnetic resonance imaging system at 2 weeks after CO exposure. As procedures for VBA, all fractional anisotropy (FA) maps obtained from DTI were spatially normalized, and FA values for all voxels in the whole CWM on normalized FA maps were statistically compared among the two patient groups and controls. RESULTS: Voxels with significant differences in FA were detected at various regions in comparisons between groups S and A and between group S and controls. In these comparisons, more voxels were detected in deep CWM, including the centrum semiovale, than in other regions. A few voxels were detected between group A and controls. Absolute FA values in the centrum semiovale were significantly lower in group S than in group A or controls. CONCLUSIONS: VBA demonstrated that CO-poisoned patients with chronic neurological symptoms had already suffered damage to various CWM regions in the subacute phase. In these regions, the centrum semiovale was suggested to be the main region damaged in the subacute phase after CO inhalation.
  • Taro Hanada, Akihiko Ishikuro, Yasushi Hasegawa, Masafumi Shimamoto, Masaaki Kobayashi, Kohsuke Kudo
    Respiratory investigation 50 (2) 62 - 5 2212-5345 2012/06 [Refereed][Not invited]
     
    Two cases of spontaneous epidural emphysema that occurred during asthmatic attacks in a 13-year-old and a 15-year-old are reported here. Epidural emphysema was diagnosed in both cases by using computed tomography (CT), and in 1 case by using magnetic resonance imaging (MRI). Neither patient had neurological findings. Both patients were discharged with no respiratory difficulties. It is generally believed that a diagnosis of epidural emphysema can only be made on CT. In this report, MRI was used to make the diagnosis of subdural emphysema, and it demonstrated that the air was localized within the epidural fat.
  • Ikuko Uwano, Kohsuke Kudo, Makoto Sasaki, Soren Christensen, Leif Østergaard, Kuniaki Ogasawara, Akira Ogawa
    Neuroradiology 54 (5) 467 - 74 0028-3940 2012/05 [Refereed][Not invited]
     
    INTRODUCTION: Computed tomography perfusion (CTP) and magnetic resonance perfusion (MRP) are expected to be usable for ancillary tests of brain death by detection of complete absence of cerebral perfusion; however, the detection limit of hypoperfusion has not been determined. Hence, we examined whether commercial software can visualize very low cerebral blood flow (CBF) and cerebral blood volume (CBV) by creating and using digital phantoms. METHODS: Digital phantoms simulating 0-4% of normal CBF (60 mL/100 g/min) and CBV (4 mL/100 g/min) were analyzed by ten software packages of CT and MRI manufacturers. Region-of-interest measurements were performed to determine whether there was a significant difference between areas of 0% and areas of 1-4% of normal flow. RESULTS: The CTP software detected hypoperfusion down to 2-3% in CBF and 2% in CBV, while the MRP software detected that of 1-3% in CBF and 1-4% in CBV, although the lower limits varied among software packages. CONCLUSION: CTP and MRP can detect the difference between profound hypoperfusion of <5% from that of 0% in digital phantoms, suggesting their potential efficacy for assessing brain death.
  • Hideo Shichinohe, Satoshi Kuroda, Kohsuke Kudo, Masaki Ito, Masahito Kawabori, Michiyuki Miyamoto, Mitsuhiro Nakanishi, Satoshi Terae, Kiyohiro Houkin
    Translational stroke research 3 (1) 99 - 106 1868-4483 2012/03 [Refereed][Not invited]
     
    Recent studies have elucidated that transplantation of the bone marrow stromal cells (BMSC) has therapeutic potential for the central nervous system (CNS) disorders. However, no imaging modalities have been established to track the engrafted cells in the CNS in clinical situation. This study aimed to investigate the ability of magnetic resonance imaging (MRI) to visualize the BMSC labeled with superparamagnetic iron oxide (SPIO). The BMSC of mice were labeled with SPIO. Various numbers of the cells were injected into the agar phantom and were visualized using a 3.0-T MR apparatus. The SPIO-labeled cells were injected into the temperature-sensitive gelation polymer (TGP) hydrogel and were cultured for 7 days. They were also visualized just after the injection and at 7 days postinjection. After a 7-day culture, they were stained with Turnbull blue technique. T2-, T2*-, and susceptibility-weighted imaging could identify minimally 1,000 cells in the agar or TGP hydrogel, although it was difficult to quantify their number on MRI. All of these sequences could track the SPIO-labeled BMSC for at least 7 days when injected into the TGP. Turnbull blue staining revealed the survival and proliferation of the SPIO-labeled BMSC in the TGP for 7 days. The findings strongly suggest that the SPIO labeling may enable to track minimally 1,000 cells engrafted in the CNS on clinical MR apparatus. These data would be valuable to consider the application of imaging technique into cell transplantation therapy for CNS disorders.
  • デジタルファントムによるCT灌流画像の低血流検出限界の評価
    上野 育子, 工藤 與亮, 佐々木 真理, 阿久津 仁美, 齊藤 絵里奈, 江原 茂
    Japanese Journal of Radiology (公社)日本医学放射線学会 30 (Suppl.I) 4 - 4 1867-1071 2012/02
  • Atsushi Kamei, Makoto Sasaki, Manami Akasaka, Nami Soga, Kohsuke Kudo, Shoichi Chida
    The Journal of pediatrics 160 (2) 342 - 4 0022-3476 2012/02 [Refereed][Not invited]
     
    Two preterm infants with athetoid cerebral palsy due to bilirubin encephalopathy were examined by magnetic resonance spectroscopic imaging at age 3 years. An increased glutamate/glutamine complex/creatine ratio was found in the basal ganglia. Chemical metabolic abnormalities of the basal ganglia were clearly demonstrated by color-coded metabolite images.
  • Takamasa Nanba, Kuniaki Ogasawara, Hideaki Nishimoto, Shunrou Fujiwara, Hiroki Kuroda, Makoto Sasaki, Kohsuke Kudo, Taro Suzuki, Masakazu Kobayashi, Kenji Yoshida, Akira Ogawa
    Cerebrovascular diseases (Basel, Switzerland) 34 (5-6) 358 - 67 1015-9770 2012 [Refereed][Not invited]
     
    BACKGROUND: Cerebral hyperperfusion after carotid endarterectomy (CEA), even when asymptomatic, often impairs cognitive function. However, conventional magnetic resonance (MR) imaging rarely demonstrates structural brain damage associated with postoperative cognitive impairment. MR diffusion tensor imaging (DTI) is potentially more sensitive for detection of white matter damage. Among the common parameters derived by DTI, fractional anisotropy (FA) is a marker of tract integrity, and mechanical disruption of axonal cylinders and loss of continuity of myelin sheaths may be responsible for reduced FA in white matter. The purpose of the present study was to determine whether postoperative cerebral white matter damage that can be detected by FA derived by DTI is associated with cerebral hyperperfusion after CEA and correlates with postoperative cognitive impairment. METHODS: In 70 patients undergoing CEA for ipsilateral internal carotid artery stenosis (≥70%), cerebral blood flow (CBF) was measured using single-photon emission computed tomography (SPECT) before and immediately after CEA and on postoperative day 3. FA values in cerebral white matter were assessed using DTI before and 1 month after surgery. These values were normalized and analyzed using statistical parametric mapping 5. In each corresponding voxel in the pre- and postoperative normalized FA maps of each patient, a postoperative FA value minus a preoperative FA value was calculated, and a voxel with postoperatively reduced FA was defined based on data obtained from healthy volunteers. The number of voxels with postoperatively reduced FA was calculated and defined as the volume with postoperatively reduced FA. Neuropsychological testing, consisting of the Wechsler Adult Intelligence Scale Revised, the Wechsler Memory Scale and the Rey-Osterreith Complex Figure test, was also performed preoperatively and after the first postoperative month. Postoperative cognitive impairment on neuropsychological testing in each patient was defined based on data obtained from patients with asymptomatic unruptured cerebral aneurysms. RESULTS: Post-CEA hyperperfusion on brain perfusion SPECT (CBF increase ≥100% compared with preoperative values) and postoperative cognitive impairment on neuropsychological testing were observed in 11 (16%) and 9 patients (13%), respectively. The volume with postoperatively reduced FA in cerebral white matter ipsilateral to surgery was significantly greater in patients with post-CEA hyperperfusion than in those without (p < 0.0001). This volume in cerebral white matter ipsilateral to surgery was also significantly associated with postoperative cognitive impairment (95% confidence interval, 1.559-8.853; p = 0.0085). CONCLUSIONS: Cerebral hyperperfusion after CEA results in postoperative cerebral white matter damage that correlates with postoperative cognitive impairment.
  • Yuri Zaitsu, Kohsuke Kudo, Satoshi Terae, Rie Yazu, Kinya Ishizaka, Noriyuki Fujima, Khin K Tha, E Mark Haacke, Makoto Sasaki, Hiroki Shirato
    Radiology 261 (3) 930 - 6 0033-8419 2011/12 [Refereed][Not invited]
     
    PURPOSE: To develop a map to detect changes in oxygen extraction fraction (OEF) utilizing susceptibility-weighted (SW) phase images and to correlate such changes in OEF with those in cerebral blood flow (CBF). MATERIALS AND METHODS: The study protocol was approved by the institutional review board, and written informed consent was obtained from all subjects. Eight healthy volunteers (mean age ± standard deviation, 29.8 years ± 4.6) were included in the study. Subjects were evaluated by using SW imaging, and the change in OEF was calculated by subtracting the image at baseline from one of the images obtained during six different conditions, including two at resting state, three different types of respiratory challenges, and one drug challenge with acetazolamide. Arterial spin labeling was carried out to measure CBF, while SW imaging was used to generate maps of change in OEF in response to a given condition. Statistical tests included one-way analysis of variance and Dunnett multiple comparisons to compare among the six conditions the magnitude of change from baseline for both OEF and CBF, by using the OEF change at resting state (resting 1) as the control. RESULTS: Hyperventilation caused a statistically significant decrease in CBF (-29.3%, P < .001) and an increase in OEF (+5.2%, P < .001) compared with the control, resting 1 (+2.2%, -0.7%, respectively). Acetazolamide caused a significant increase in CBF (+39.7%, P < .001) and a decrease in OEF (-3.4%, P = .040). Carbogen also induced a CBF increase (+16.2%); however, the change was not significant (P = .090), even though OEF decreased significantly (-4.2%, P = .003). Oxygen administration resulted in a significant CBF decrease (-27.2%, P < .001), whereas OEF showed no significant difference (-0.6%, P > .99). CONCLUSION: Maps of changes in OEF generated from SW phase images revealed changes in OEF corresponding to anticipated changes in CBF induced by various conditions; SW phase imaging might, in the future, be applied to evaluate cerebrovascular and other cerebral disorders in which changes in oxygen metabolism are important for planning therapeutic strategies.
  • Diffusion tensor imaging-voxel-based analysisを用いた一酸化炭素中毒亜急性期白質障害部位の特定
    藤原 俊朗, 別府 高明, 西本 英明, 村上 寿之, 三條 克己, 工藤 薫, 森 潔, 工藤 與亮, 佐々木 真理, 小川 彰, 小笠原 邦昭
    脳循環代謝 日本脳循環代謝学会 23 (1) 163 - 163 0915-9401 2011/11 [Not refereed][Not invited]
  • Noriko Oyama-Manabe, Naoki Ishimori, Hiroyuki Sugimori, Marc Van Cauteren, Kohsuke Kudo, Osamu Manabe, Tomoyuki Okuaki, Tamotsu Kamishima, Yoichi M Ito, Hiroyuki Tsutsui, Khin Khin Tha, Satoshi Terae, Hiroki Shirato
    European radiology 21 (11) 2362 - 8 0938-7994 2011/11 [Refereed][Not invited]
     
    OBJECTIVES: To investigate whether subendocardial and transmural myocardial infarction can be identified and differentiated using the peak circumferential and longitudinal strains measured by fast strain-encoded (SENC). METHODS: Nineteen patients with ischemic heart diseases underwent imaging with fast SENC and late gadolinium enhancement (LGE) MRI at 3 T. Fast SENC measurements were performed in three short-axis slices (basal, mid-ventricular and apical levels) and one long-axis view (four-chamber) to assess peak longitudinal and circumferential systolic strains. RESULTS: All patients showed myocardial infarction with an average of 7 positive LGE segments. A total of 304 segments for longitudinal strains (LS) and 114 segments for circumferential strains (CS) could be analysed. Positive LGE segments showed lower peak CS and LS compared with the no LGE segments (P < 0.0001 for both). Segments with subendocardial infarction showed reduced CS and LS compared with the no LGE segments (P < 0.0001 for both). There was a significant difference in CS between subendocardial and transmural infarct segments (P = 0.03), but no significant difference in LS between them (P = 0.64). CONCLUSIONS: Fast SENC can identify old myocardial infarction and differentiate subendocardial from transmural infarction.
  • Takaaki Beppu, Makoto Sasaki, Kohsuke Kudo, Akira Kurose, Masaru Takeda, Hiroshi Kashimura, Akira Ogawa, Kuniaki Ogasawara
    Journal of neuro-oncology 103 (3) 619 - 27 0167-594X 2011/07 [Refereed][Not invited]
     
    Tumor grade differentiation is often difficult using routine neuroimaging alone. Computed tomography perfusion imaging (CTP) provides quantitative information on tumor vasculature that closely parallels the degree of tumor malignancy. This study examined whether CTP is useful for preoperatively predicting the grade of malignancy in glioma showing no enhancement on contrast-enhanced magnetic resonance imaging (MRI). Subjects comprised 17 patients with supratentorial glioma without enhancement on MRI. CTP was performed preoperatively, and absolute values and normalized ratios of parameters were calculated. Postoperatively, subjects were classified into two groups according to histological diagnosis of grade 3 (G3) glioma or grade 2 (G2) glioma. Absolute values and normalized ratios for each parameter were compared between G3 and G2. Accuracies of normalized ratios for cerebral blood flow (nCBF) and cerebral blood volume (nCBV) in predicting a diagnosis of G3 were assessed. In addition, nCBV was compared between diffuse astrocytoma, G2 oligodendroglial tumor (OT), and G3 OT. Values for nCBF and nCBV differed significantly between G3 and G2. Using nCBV of 1.6 as a cutoff, specificity and sensitivity for distinguishing G3 were 83.3% and 90.9%, respectively. No significant difference in nCBV was seen between diffuse astrocytoma and G2 OT, whereas differences were noted between G2 and G3 OTs, and between diffuse astrocytoma and G3 OT. CTP offers a useful method for differentiating between G3 and G2 in nonenhancing gliomas.
  • Shunrou Fujiwara, Makoto Sasaki, Tsukasa Wada, Kohsuke Kudo, Ryonoshin Hirooka, Daiya Ishigaki, Yasumasa Nishikawa, Ayumi Ono, Mao Yamaguchi, Kuniaki Ogasawara
    Journal of neuroimaging : official journal of the American Society of Neuroimaging 21 (2) e102-8 - e108 1051-2284 2011/04 [Refereed][Not invited]
     
    PURPOSE: To detect diffusion abnormalities in the trigeminal nerves of patients with trigeminal neuralgia (TN) caused by neurovascular compression (NVC) by using a high-resolution diffusion tensor imaging (HR-DTI) technique. METHODS: Thirteen patients with TN and 14 healthy controls underwent HR-DTI scanning. After extracting the trigeminal nerve using a tractography technique, we measured the fractional anisotropy (FA) and apparent diffusion coefficient (ADC), and compared the contralateral ratios (CR) of these parameters between the patients and controls, and correlated these ratios with the cross-sectional areas of the nerves. RESULTS: The CRs of the FA values for the trigeminal nerves of the patients (1.00±0.15) had significantly higher variance than those of healthy controls (1.00±0.05) (P<.05) and showed a positive correlation with the cross-sectional area of the nerves (r=0.81). In contrast, the CRs of the ADC values were not significantly different between the two groups (1.02±0.10 and 1.01±0.08, respectively) and had no significant correlation with cross-sectional area. CONCLUSION: HR-DTI can detect an alteration in the relative FA values of affected trigeminal nerves and a correlation with atrophic changes in patients with NVC-induced TN.
  • Kohsuke Kudo, Makoto Sasaki, Leif Østergaard, Soren Christensen, Ikuko Uwano, Masako Suzuki, Kuniaki Ogasawara, Hiroki Shirato, Akira Ogawa
    Journal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism 31 (3) 908 - 12 0271-678X 2011/03 [Refereed][Not invited]
     
    The time-to-maximum of the tissue residue function (T(max)) perfusion index has proven very predictive of infarct growth in large clinical trials, yet its dependency on simple tracer delays remains unknown. Here, we determine the dependency of computed tomography (CT) perfusion (CTP) T(max) estimates on tracer delay using a range of deconvolution techniques and digital phantoms. Digital phantom data sets simulating the tracer delay were created from CTP data of six healthy individuals, in which time frames of the left cerebral hemisphere were shifted forward and backward by up to ±5 seconds. These phantoms were postprocessed with three common singular value decomposition (SVD) deconvolution algorithms-standard SVD (sSVD), block-circulant SVD (bSVD), and delay-corrected SVD (dSVD)-with an arterial input function (AIF) obtained from the right middle cerebral artery (MCA). The T(max) values of the left hemisphere were compared among different tracer delays and algorithms by a region of interest-based analysis. The T(max) values by sSVD were positively correlated with 'positive shifts' but unchanged with 'negative shifts,' those by bSVD had an excellent positive linear correlation with both positive and negative shifts, and those by dSVD were relatively constant, although slightly increased with the positive shifts. The T(max) is a parameter highly dependent on tracer delays and deconvolution algorithm.
  • Makoto Sasaki, Kohsuke Kudo, Kaneyoshi Honjo, Jin-Qing Hu, Hai-Bin Wang, Katsuya Shintaku
    Journal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism 31 (2) 448 - 56 0271-678X 2011/02 [Refereed][Not invited]
     
    By optimizing thresholds, we identified the perfusion-weighted magnetic resonance imaging (PWI) parameters that accurately predict final infarct volume and neurologic outcome in a primate model of permanent middle cerebral artery (MCA) occlusion. Ten cynomolgus monkeys underwent PWI and diffusion-weighted imaging (DWI) at 3 and 47 hours, respectively, after right MCA occlusion using platinum coils, and were killed at 48 hours. Volumes of the hypoperfused areas on PWI were automatically measured using different thresholds and 11 parametric maps to determine the optimum threshold (at which least difference was found between the average volumes on PWI and those determined using specimens or DWI). In the case of arrival time (AT), cerebral blood volume (CBV), time to peak (TTP), time to maximum (T(max)), and cerebral blood flow (CBF) determined using deconvolution techniques, the volume of the hypoperfused area significantly correlated with the infarct volumes and the neurologic deficit scores with small variations, whereas in the case of mean transit time and nondeconvolution CBF, relatively poor correlations with large variations were seen. At optimum threshold, AT, CBV, TTP, T(max), and deconvolution CBF can accurately predict the final infarct volume and neurologic outcome in monkeys with permanent MCA occlusion.
  • Noriyuki Fujima, Kohsuke Kudo, Satoshi Terae, Kinya Ishizaka, Rie Yazu, Yuri Zaitsu, Khin Khin Tha, Daisuke Yoshida, Akiko Tsukahara, Mark E Haacke, Makoto Sasaki, Hiroki Shirato
    NeuroImage 54 (1) 344 - 9 1053-8119 2011/01/01 [Refereed][Not invited]
     
    Susceptibility-weighted imaging (SWI) has been used for quantitative and non-invasive measurement of blood oxygen saturation in the brain. In this study, we used SWI for quantitative measurement of oxygen saturation in the spinal vein to look for physiological- or caffeine-induced changes in venous oxygenation. SWI measurements were obtained for 5 healthy volunteers using 1.5-T MR units, under 1) 3 kinds of physiological load (breath holding, Bh; hyperventilation, Hv; and inspiration of highly concentrated oxygen, Ox) and 2) caffeine load. Oxygen saturation in the anterior spinal vein (ASV) was calculated. We evaluated changes in oxygen saturation induced by physiological load. We also evaluated the time-course of oxygen saturation after caffeine intake. For the physiological load measurements, the average oxygen saturation for the 5 subjects was significantly lower in Hv (0.75) and significantly higher in Bh (0.84) when compared with control (0.80). There was no significant difference between Ox (0.81) and control. Oxygen saturation gradually decreased after caffeine intake. The average values of oxygen saturation were 0.79 (0 min), 0.76 (20 min), 0.74 (40 min), and 0.73 (60 min), respectively. We demonstrated a significant difference in oxygen saturation at 40 and 60 min after caffeine intake when compared with 0 min. In conclusion, we demonstrated the feasibility of using SWI for non-invasive measurement of oxygen saturation in the spinal vein. We showed changes in oxygen saturation under physiological as well as caffeine load and suggest that this method is a useful tool for the clinical evaluation of spinal cord oxygenation.
  • Yusuke Shimoda, Kohsuke Kudo, Satoshi Kuroda, Yuri Zaitsu, Nobuyuki Fujima, Satoshi Terae, Makoto Sasaki, Kiyohiro Houkin
    Magnetic resonance in medical sciences : MRMS : an official journal of Japan Society of Magnetic Resonance in Medicine 10 (1) 49 - 52 1347-3182 2011 [Refereed][Not invited]
     
    We performed magnetic resonance angiography (MRA) and susceptibility-weighted imaging (SWI) to observe cerebral changes during a migraine attack in a 28-year-old man. MRA revealed regional arterial spasm, and findings of SWI were consistent with decreased blood flow and/or venous dilatation. Because these noninvasive techniques can be performed repeatedly at short intervals, they can be useful for evaluating hemodynamic changes during and after migraine attacks.
  • Masako Suzuki, Kohsuke Kudo, Makoto Sasaki, Satoshi Takahashi, Jyunko Takahashi, Noriyuki Fujima, Ikuko Uwano, Hisashi Yonezawa, Masako Kudo, Hikoaki Fukaura, Naoki Ishizuka, Yasuo Terayama
    Magnetic resonance in medical sciences : MRMS : an official journal of Japan Society of Magnetic Resonance in Medicine 10 (3) 185 - 92 1347-3182 2011 [Refereed][Not invited]
     
    PURPOSE: Susceptibility-weighted (SW) imaging is a magnetic resonance (MR) imaging technique reported effective in visualizing multiple sclerosis (MS) plaques, but its capacity to distinguish active plaques remains unclear. We evaluated active plaque detection by SW compared with contrast-enhanced MR imaging. METHODS: We prospectively examined 11 patients using a 3-tesla scanner. Two neuroradiologists independently evaluated signal changes of plaques and accompanying low signal rims in 74 plaques on various SW images (magnitude, phase, and minimum intensity projection [minIP]), and on contrast-enhanced T(1)-weighted images (T(1)WI). We correlated signal alterations on various SW images and contrast enhancement on T(1)WI using Fisher's exact test and calculated sensitivity and specificity for predicting gadolinium enhancement. RESULTS: Only changes in plaque signal on SW magnitude images correlated significantly with contrast enhancement of the plaques (P=0.008), and high signal intensity had 0.556 sensitivity and 0.787 specificity for predicting contrast-enhanced plaques. Furthermore, plaques with rims of low signal showed sensitivity of 0.296 and specificity of 0.957. CONCLUSIONS: Susceptibility-weighted magnitude, but not phase or minIP, images can predict MS plaques with contrast enhancement with high specificity.
  • 高解像度磁気共鳴画像を用いた穿通枝領域梗塞における中大脳動脈・脳底動脈の動脈硬化性プラークの検出 磁気共鳴血管造影との比較(Detection of atherosclerotic plaques in middle cerebral and basilar arteries in large infarctions of perforating artery territories using high-resolution magnetic resonance plaque imaging at 3T: comparison with magnetic resonance angiography)
    桂 永行, 佐々木 真理, 石橋 靖宏, 米澤 久司, 工藤 雅子, 工藤 與亮, 高橋 純子, 高橋 智, 寺山 靖夫
    岩手医学雑誌 62 (5) 353 - 362 0021-3284 2010/12 [Refereed][Not invited]
     
    穿通枝領域のアテローム血栓性脳梗塞は、頭蓋内動脈の狭窄を伴わない場合,診断に苦慮することがある.そこで,穿通枝脳梗塞における高解像度MRIの頭蓋内動脈プラーク検出能をMRAの狭窄病変検出能と比較した.基底核・橋穿通枝領域のアテローム血栓性脳梗塞疑い患者18名に高解像度MRIとMRAを撮像し,中大脳動脈水平部(M1),脳底動脈のプラーク・狭窄の有無を視覚的に判定した.高解像度MRIにおけるプラーク検出率は72〜83%で,MRAにおける狭窄性変化(50%,うち高度狭窄17%)に比し高率であった.脳底動脈では高解像度MRIのプラーク検出率は89〜100%で,MRAの44%に比し有意に高かったが,M1では56〜66%で,MRAと同程度であった.高解像度MRIはMRAで頭蓋内動脈狭窄を認めない例でもプラークを検出することができ,穿通枝領域脳梗塞の病型診断に有用と考えられる.(著者抄録)
  • Toshiyuki Murakami, Kuniaki Ogasawara, Yoshichika Yoshioka, Daiya Ishigaki, Makoto Sasaki, Kohsuke Kudo, Kenta Aso, Hideaki Nishimoto, Masakazu Kobayashi, Kenji Yoshida, Akira Ogawa
    Radiology 256 (3) 924 - 31 0033-8419 2010/09 [Refereed][Not invited]
     
    PURPOSE: To determine whether brain temperature measured by using preoperative proton magnetic resonance (MR) spectroscopy could help identify patients at risk for cerebral hyperperfusion after carotid endarterectomy (CEA). MATERIALS AND METHODS: Institutional review board approval and informed consent were obtained. Acquisition of proton MR spectroscopic data by using point-resolved spectroscopy without water suppression was performed before CEA in the bilateral cerebral hemispheres of 84 patients with unilateral internal carotid artery stenosis (> or =70%) and without contralateral internal carotid artery steno-occlusive disease. Brain temperature was calculated from the chemical shift difference between water and N-acetylaspartate signals at proton MR spectroscopy. Cerebral blood flow (CBF) was also measured by using single photon emission computed tomography and N-isopropyl-p-[(123)I]-iodoamphetamine before and immediately after CEA and on the 3rd postoperative day. The relationship between each variable and the development of post-CEA hyperperfusion (CBF increase > or = 100% compared with preoperative values) was evaluated with univariate statistical analysis followed by multivariate analysis. RESULTS: A linear correlation was observed between preoperative brain temperature difference (the value in the affected hemisphere minus the value in the contralateral hemisphere) and increases in CBF immediately after CEA (r = 0.763 and P < .001) when the preoperative brain temperature difference was greater than 0. Cerebral hyperperfusion immediately after CEA was observed in nine patients (11%). Elevated preoperative brain temperature difference was the only significant independent predictor of post-CEA hyperperfusion. When elevated brain temperature difference was defined as a marker of hemodynamic impairment in the affected cerebral hemisphere, use of preoperative brain temperature difference resulted in 100% sensitivity and 87% specificity, with a 47% positive predictive value and a 100% negative predictive value for the prediction of post-CEA hyperperfusion. Hyperperfusion syndrome developed on the 3rd and 4th postoperative days in two of the nine patients who exhibited hyperperfusion immediately after CEA. CONCLUSION: Brain temperature measured by using preoperative proton MR spectroscopy may help identify patients at risk for post-CEA cerebral hyperperfusion.
  • Fumio Yamashita, Makoto Sasaki, Satoshi Takahashi, Hiroshi Matsuda, Kohsuke Kudo, Shinsuke Narumi, Yasuo Terayama, Takashi Asada
    NEURORADIOLOGY 52 (5) 381 - 386 0028-3940 2010/05 [Refereed][Not invited]
     
    We attempted to detect alterations in the cerebrospinal fluid (CSF) space in patients with idiopathic normal pressure hydrocephalus (iNPH) using voxel-based morphometry (VBM). We obtained sagittal volume images of the entire head by three-dimensional T1-weighted magnetic resonance imaging and compared the regional distribution of CSF in 12 patients with iNPH, 14 patients with Alzheimer's disease (AD), and 17 healthy individuals using VBM with automatically extracted CSF objects. VBM demonstrated significant widening at the lateral ventricles and Sylvian fissures and narrowing of the CSF space at the high convexity/midline areas in iNPH patients, compared to the AD patients and healthy controls (p < 0.05, after correction with a false-discovery rate). In addition, the ratio of the CSF volume in the lateral ventricle/Sylvian fissure area to that in the high convexity/midline area in iNPH patients (3.9 +/- 1.2) was remarkably greater than that in AD patients (1.2 +/- 0.3) and controls (0.9 +/- 0.3; one-way ANOVA, p < 0.001; post hoc Tukey's test, p < 0.001); we could discriminate iNPH patients from those in the other two groups without any overlap, when using a cutoff level of 1.9. VBM using CSF objects can be used to delineate the characteristic alteration of the CSF space in iNPH patients, which has been evaluated by visual interpretation.
  • Khin K Tha, Satoshi Terae, Ichiro Yabe, Tamaki Miyamoto, Hiroyuki Soma, Yuri Zaitsu, Noriyuki Fujima, Kohsuke Kudo, Hidenao Sasaki, Hiroki Shirato
    Radiology 255 (2) 563 - 9 0033-8419 2010/05 [Refereed][Not invited]
     
    PURPOSE: To determine whether diffusion-tensor (DT) imaging can demonstrate microstructural white matter abnormalities of multiple system atrophy (MSA) and to correlate these imaging findings with clinical signs and symptoms. MATERIALS AND METHODS: Institutional review board approval and written informed consent were obtained. DT imaging was performed in 16 patients with MSA with predominant cerebellar symptoms (MSA-C) (mean age, 60.0 years + or - 5.1 [standard deviation]; range, 51-69 years) and 16 age-matched healthy subjects. Fractional anisotropy (FA) and mean diffusivity (MD) were compared voxel-by-voxel between the two groups by using a two-sample t test. Overlap maps were created to illustrate areas with FA and MD alterations. Correlation between DT imaging indexes and Barthel index score, scale for assessment and rating of ataxia (SARA) score, severity of orthostatic hypotension, age of disease onset, and disease duration was tested by using Spearman rank or Pearson product-moment correlation analysis. T2-weighted and proton density-weighted images of the patients were visually assessed. RESULTS: Widespread areas of FA reduction and MD elevation were observed in supra- and infratentorial white matter structures in patients with MSA (P < .05, false discovery rate corrected). Significant correlation (P < .01) between DT imaging indexes and Barthel index score, SARA score, severity of orthostatic hypotension, and disease duration was observed for multiple areas with FA and/or MD alterations. T2-weighted and proton density-weighted images showed no significant abnormality in supratentorial white matter. CONCLUSION: DT imaging may help identify the microstructural white matter abnormalities of MSA-C. DT imaging may be useful for severity assessment of MSA-C.
  • Noriyuki Fujima, Kohsuke Kudo, Satoshi Terae, Kazutoshi Hida, Kinya Ishizaka, Yuri Zaitsu, Takeshi Asano, Daisuke Yoshida, Khin Khin Tha, E Mark Haacke, Makoto Sasaki, Hiroki Shirato
    Radiology 254 (3) 891 - 9 0033-8419 2010/03 [Refereed][Not invited]
     
    PURPOSE: To evaluate the efficacy of susceptibility-weighted (SW) magnetic resonance (MR) imaging for the assessment of the posttreatment change in oxygen saturation in the draining vein in patients with spinal arteriovenous malformation (AVM). MATERIALS AND METHODS: The study protocol was approved by the institutional review board, and written informed consent was obtained from all subjects. SW imaging was performed in 11 patients with spinal AVM before and after surgical or endovascular treatment. Eleven healthy subjects were included as a control group. A four-grade response scale was used for the visual assessment of the anterior spinal vein (ASV). For quantitative analysis, the phase value of the ASV was measured and oxygen saturation was calculated. Nonparametric multigroup comparison for visual assessment and one-way analysis of variance for quantitative measurement of oxygen saturation were used as statistical tests for comparison among three groups (pretreatment patients, posttreatment patients, and control subjects). RESULTS: Complete shunt occlusion in all patients was confirmed by using conventional angiography. For visual assessment, the average score of the pretreatment group was significantly less than that of the posttreatment and control groups. For quantitative analysis, the average oxygen saturation of the pretreatment group was significantly higher than that of the posttreatment and control groups, while no significant difference was observed between the posttreatment and control groups. CONCLUSION: After treatment, normalization of increased oxygen saturation was noninvasively observed by using SW imaging in patients with spinal AVM. SW imaging can be a useful tool for the assessment of treatment efficacy in patients with spinal AVM. (c) RSNA, 2010.
  • Makoto Sasaki, Eri Shibata, Kotaro Ohtsuka, Jin Endoh, Kohsuke Kudo, Shinsuke Narumi, Akio Sakai
    NEURORADIOLOGY 52 (2) 83 - 89 0028-3940 2010/02 [Refereed][Not invited]
     
    Fast spin-echo (FSE) T1-weighted (T1W) magnetic resonance imaging (MRI) at 3T, which is sensitive to neuromelanin-related contrast, can quantitatively detect signal alterations in the locus ceruleus (LC) and the substantia nigra pars compacta (SNc) of depressive and schizophrenic patients; however, its qualitative diagnostic performance remains unknown. We investigated whether visual interpretation of semiquantitative color maps can be used for discriminating between depressive and schizophrenic patients and healthy individuals. We retrospectively examined 23 patients with major depression, 23 patients with schizophrenia, and 23 age-matched healthy controls by using a FSE-T1W MRI technique. Semiquantitative color maps of sections through the LC and SNc were visually interpreted by nine raters using a continuous confidence rating scale for receiver operating characteristic (ROC) analysis. The area under the ROC curve (Az), which reflects the performance in differentiating between depressive patients and controls, was 0.88, and the sensitivity and specificity at the maximum likelihood were 76% and 83%, respectively. In contrast, the Az value, sensitivity, and specificity values between schizophrenics and controls and between depressives and schizophrenics were 0.66 and 0.69, 42% and 48%, and 82% and 84%, respectively. Semiquantitative, color-coded FSE-T1W MRI at 3T can be used for visually differentiating depressive patients from healthy individuals with a substantially high likelihood, but this technique cannot be applied to distinguish schizophrenic patients from the other two groups.
  • Kohsuke Kudo, Makoto Sasaki, Kei Yamada, Suketaka Momoshima, Hidetsuna Utsunomiya, Hiroki Shirato, Kuniaki Ogasawara
    Radiology 254 (1) 200 - 9 2010/01 [Refereed][Not invited]
     
    PURPOSE: To examine the variability in the qualitative and quantitative results of computed tomographic (CT) perfusion imaging generated from identical source data of stroke patients by using commercially available software programs provided by various CT manufacturers. MATERIALS AND METHODS: Institutional review board approval and informed consent were obtained. CT perfusion imaging data of 10 stroke patients were postprocessed by using five commercial software packages, each of which had a different algorithm: singular-value decomposition (SVD), maximum slope (MS), inverse filter (IF), box modulation transfer function (bMTF), and by using custom-made original software with standard (sSVD) and block-circulant (bSVD) SVD methods. Areas showing abnormalities in cerebral blood flow (CBF), mean transit time (MTT), and cerebral blood volume (CBV) were compared with each other and with the final infarct areas. Differences among the ratios of quantitative values in the final infarct areas and those in the unaffected side were also examined. RESULTS: The areas with CBF or MTT abnormalities and the ratios of these values significantly varied among software, while those of CBV were stable. The areas with CBF or MTT abnormalities analyzed by using SVD or bMTF corresponded to those obtained with delay-sensitive sSVD, but overestimated the final infarct area. The values obtained from software by using MS or IF corresponded well with those obtained from the delay-insensitive bSVD and the final infarct area. Given the similarities between CBF and MTT, all software were separated in two groups (ie, sSVD and bSVD). The ratios of CBF or MTTs correlated well within both groups, but not across them. CONCLUSION: CT perfusion imaging maps were significantly different among commercial software even when using identical source data, presumably because of differences in tracer-delay sensitivity.
  • Kinya Ishizaka, Kohsuke Kudo, Noriyuki Fujima, Yuri Zaitsu, Rie Yazu, Khin Khin Tha, Satoshi Terae, E Mark Haacke, Makoto Sasaki, Hiroki Shirato
    Journal of magnetic resonance imaging : JMRI 31 (1) 32 - 8 1053-1807 2010/01 [Refereed][Not invited]
     
    PURPOSE: To evaluate the visualization of the spinal veins using susceptibility-weighted imaging (SWI). MATERIALS AND METHODS: A 1.5-T magnet equipped with a spine matrix coil was used. Axial SWI scans of 20 healthy volunteers were obtained with a three-dimensional fast low-angle shot (3D-FLASH) sequence. Maximum intensity projection (MIP) of the phase images were reconstructed and five MIP images (at the levels of T11, T11/12, T12, T12/L1, and L1) were selected for the evaluation. The anterior median vein (AMV), posterior median vein (PMV), anterior radiculomedullary vein (ARV), posterior radiculomedullary vein (PRV), and sulcal vein (SV) were evaluated using a 4-grade scale (0, none; 1, weak; 2, moderate; and 3, prominent). RESULTS: The AMV was detected in all the subjects (100%). The detection rates of the other veins were lower: PMV, 65%; right ARV, 45%; left ARV, 15%; right PRV, 10%; left PRV, 30%; and SV, 0%. The average scores for AMV, PMV, right ARV, left ARV, right PRV, left PRV, and SV were 0.98, 0.24, 0.20, 0.08, 0.08, 0.14, and 0, respectively. CONCLUSION: SWI of the spine is feasible. The extrinsic spinal veins can be visualized by SWI without using contrast materials.
  • Yuri Zaitsu, Satoshi Terae, Kohsuke Kudo, Khin Khin Tha, Mineji Hayakawa, Noriyuki Fujima, Daisuke Yoshida, Akiko Tsukahara, Hiroki Shirato
    Journal of computer assisted tomography 34 (1) 107 - 12 0363-8715 2010/01 [Refereed][Not invited]
     
    Cerebral fat embolism (CFE) causes microinfarcts, vasogenic edema, and petechiae in the brain. Conventional magnetic resonance imaging has been reported to effectively visualize microinfarcts and vasogenic edema in CFE, but not petechiae. We report 3 cases of CFE in which susceptibility-weighted imaging distinctly demonstrated multiple minute hypointense foci in the brain, which were interpreted as petechiae, susceptibility-weighted imaging is a useful adjunct to conventional magnetic resonance imaging for the evaluation of CFE.
  • Benjamin Hotter, Sandra Pittl, Martin Ebinger, Gabriele Oepen, Kati Jegzentis, Kohsuke Kudo, Michal Rozanski, Wolf U. Schmidt, Peter Brunecker, Chao Xu, Peter Martus, Matthias Endres, Gerhard J. Jungehuelsing, Arno Villringer, Jochen B. Fiebach
    BMC NEUROLOGY 9 60  1471-2377 2009/12 [Refereed][Not invited]
     
    Background: The mismatch between diffusion weighted imaging (DWI) lesion and perfusion imaging (PI) deficit volumes has been used as a surrogate of ischemic penumbra. This pathophysiology-orientated patient selection criterion for acute stroke treatment may have the potential to replace a fixed time window. Two recent trials - DEFUSE and EPITHET - investigated the mismatch concept in a multicenter prospective approach. Both studies randomized highly selected patients (n = 74/n = 100) and therefore confirmation in a large consecutive cohort is desirable. We here present a single-center approach with a 3T MR tomograph next door to the stroke unit, serving as a bridge from the ER to the stroke unit to screen all TIA and stroke patients. Our primary hypothesis is that the prognostic value of the mismatch concept is depending on the vessel status. Primary endpoint of the study is infarct growth determined by imaging, secondary endpoints are neurological deficit on day 5-7 and functional outcome after 3 months. Methods and design: 1000Plus is a prospective, single centre observational study with 1200 patients to be recruited. All patients admitted to the ER with the clinical diagnosis of an acute cerebrovascular event within 24 hours after symptom onset are screened. Examinations are performed on day 1, 2 and 5-7 with neurological examination including National Institute of Health Stroke Scale (NIHSS) scoring and stroke MRI including T2*, DWI, TOF-MRA, FLAIR and PI. PI is conducted as dynamic susceptibility-enhanced contrast imaging with a fixed dosage of 5 ml 1 M Gadobutrol. For post-processing of PI, mean transit time (MTT) parametric images are determined by deconvolution of the arterial input function (AIF) which is automatically identified. Lesion volumes and mismatch are measured and calculated by using the perfusion mismatch analyzer (PMA) software from ASIST-Japan. Primary endpoint is the change of infarct size between baseline examination and day 5-7 follow up. Discussions: The aim of this study is to describe the incidence of mismatch and the predictive value of PI for final lesion size and functional outcome depending on delay of imaging and vascular recanalization. It is crucial to standardize PI for future randomized clinical trials as for individual therapeutic decisions and we expect to contribute to this challenging task.
  • K K Tha, S Terae, K Kudo, K Miyasaka
    The British journal of radiology 82 (979) 610 - 4 0007-1285 2009/07 [Refereed][Not invited]
     
    The fluid-attenuated inversion recovery imaging sequence is a widely used MRI sequence of the brain. It is an inversion recovery pulse sequence, designed to suppress signals from the cerebrospinal fluid. It is highly sensitive for detection of lesions adjacent to or within the cerebrospinal fluid, associated with T(2) prolongation or T(1) shortening. The term "hyperintense cerebrospinal fluid" is used to describe failed suppression or hyperintensity of cerebrospinal fluid on fluid-attenuated inversion recovery imaging of the brain. It is often encountered in many important pathological conditions, including subarachnoid haemorrhage, meningitis and leptomeningeal metastasis. However, certain non-pathological states in which there is no definite cerebrospinal fluid abnormality can also present with hyperintense cerebrospinal fluid. Correct interpretation of abnormalities is important to arrive at an appropriate diagnosis. This pictorial review provides fluid-attenuated inversion recovery images of hyperintense cerebrospinal fluid of the brain and describes distinguishing features, focusing on non-pathological conditions.
  • Masahito Kawabori, Satoshi Kuroda, Kohsuke Kudo, Satoshi Terae, Makoto Kaneda, Naoki Nakayama, Yoshinobu Iwasaki
    Neurologia medico-chirurgica 49 (6) 248 - 51 0470-8105 2009/06 [Refereed][Not invited]
     
    An 11-year-old female receiving treatment for acute lymphoblastic leukemia presented with superior sagittal sinus (SSS) thrombosis. T(1)-weighted, T(2)-weighted, and fluid-attenuated inversion recovery magnetic resonance (MR) imaging, and MR venography showed that the SSS was totally occluded by thrombus. Susceptibility-weighted MR imaging showed hypointense thrombus in the SSS and markedly dilated cortical veins over the bilateral cerebral hemispheres. Two days later, her symptoms had slightly resolved. Iodine-123 N-isopropyl-p-iodoamphetamine single photon emission computed tomography showed marked decrease of cerebral blood flow in the bilateral frontal lobes, indicating that venous congestion had disturbed the cerebral hemodynamics. MR venography showed that the SSS was still mostly occluded, but susceptibility-weighted imaging showed that the dilation of the cortical veins was less marked, suggesting that collateral venous routes had gradually developed. The finding of dilated cortical veins had almost disappeared at 28 days after the onset. Susceptibility-weighted imaging can be used as a non-invasive method to monitor the severity of venous congestion caused by cerebral venous sinus thrombosis.
  • K K Tha, S Terae, K Kudo, K Miyasaka
    The British journal of radiology 82 (977) 426 - 34 0007-1285 2009/05 [Refereed][Not invited]
     
    The fluid-attenuated inversion recovery imaging sequence is a widely used MRI sequence of the brain. It is an inversion recovery pulse sequence, designed to suppress signals from the cerebrospinal fluid. It is highly sensitive in detection of lesions adjacent to or within the cerebrospinal fluid associated with T(2) prolongation or T(1) shortening. The term "hyperintense cerebrospinal fluid" is used to describe failed suppression, or hyperintensity, of cerebrospinal fluid on fluid-attenuated inversion recovery imaging of the brain. It is often encountered in many important pathological conditions, including subarachnoid haemorrhage, meningitis and leptomeningeal metastasis. However, certain non-pathological states in which there is no definite cerebrospinal fluid abnormality can also present with hyperintense cerebrospinal fluid. Correct interpretation of abnormalities is important to arrive at an appropriate diagnosis. This pictorial review provides fluid-attenuated inversion recovery images of hyperintense cerebrospinal fluid of the brain and describes distinguishing features. Part I features pathological conditions whereas Part II focuses on non-pathological conditions.
  • Kohsuke Kudo, Makoto Sasaki, Kuniaki Ogasawara, Satoshi Terae, Shigeru Ehara, Hiroki Shirato
    Radiology 251 (1) 241 - 9 0033-8419 2009/04 [Refereed][Not invited]
     
    Institutional review board approval and informed consent were obtained. The purpose was to evaluate the differences in tracer delay-induced effects of various deconvolution algorithms for computed tomographic (CT) perfusion imaging by using digital phantoms created from actual source data. Three methods of singular value decomposition (SVD) were evaluated. For standard SVD (sSVD), the delays induced significant errors in cerebral blood flow and mean transit time. In contrast, for block-circulant SVD (bSVD), these values remained virtually unchanged, whereas for delay-corrected SVD (dSVD), mild changes were observed. bSVD was superior to sSVD and dSVD for avoiding the tracer delay-induced effects in CT perfusion imaging.
  • M. Sasaki, K. Kudo, K. Ogasawara, S. Fujiwara
    AMERICAN JOURNAL OF NEURORADIOLOGY 30 (1) 188 - 193 0195-6108 2009/01 [Refereed][Not invited]
     
    BACKGROUND AND PURPOSE: Reliability of CT perfusion (CTP) algorithms has not been fully validated. We investigated whether the cerebral blood flow (CBF) values obtained by using a dynamic CTP technique with a tracer delay-insensitive deconvolution algorithm are more accurate than those obtained by using CTP with delay-sensitive algorithms in unilateral cerebrovascular steno-occlusive disease, when compared with those generated by quantitative single-photon emission CT (SPECT). MATERIALS AND METHODS: Using CTP and iodine-123-N-isopropyl-p-iodoamphetamine SPECT with an autoradiographic quantification technique, we examined 20 patients with suggested hemodynamic ischemia due to stenosis or occlusion of the unilateral internal carotid or middle cerebral artery. The algorithms used for CTP included delay-insensitive block-circulant singular value decomposition (SVD) (bSVD) and delay-sensitive standard SVD (sSVD) and box-modulation transfer function (bMTF). RESULTS: Absolute CBF values obtained by using CTP with bSVD were significantly lower than those obtained with SPECT, but the ratios to the nonaffected side were significantly correlated to the quantitative SPECT values with significant agreements, particularly when the arterial input function was obtained from the unaffected side. Contrastingly, CBF ratios with sSVD and bMTF were significantly underestimated, and no significant agreement was determined between CTP with sSVD or bMTF and SPECT, though there were substantial correlations between them in some parameters. CONCLUSIONS: With the CTP technique, the insensitivity of the deconvolution algorithm to the tracer-delay effect appears to be essential for estimating semiquantitative CBF values in patients with unilateral steno-occlusive lesions.
  • Makoto Sasaki, Eri Shibata, Koujiro Tohyama, Kohsuke Kudo, Jin Endoh, Kotaro Otsuka, Akio Sakai
    Neuroreport 19 (17) 1649 - 54 0959-4965 2008/11/19 [Refereed][Not invited]
     
    By using high-resolution, conventional, and neuromelanin-sensitive magnetic resonance imaging techniques, we reviewed the normal anatomy of the nuclei consisting of monoamine neurons such as dopaminergic, noradrenergic, and serotoninergic neurons and noted the changes in these nuclei that occur in some degenerative and psychiatric disorders. Multimodal MR images can directly or indirectly help in identifying the substantia nigra, locus ceruleus, and raphe nuclei that contain monoamine neurons. Neuromelanin-sensitive magnetic resonance imaging can detect signal alterations in the substantia nigra pars compacta and/or locus ceruleus that occur in Parkinson's disease and psychiatric disorders such as depression and schizophrenia. This technique seems to be promising for the noninvasive evaluation of the pathological or functional changes in the monoamine system that occur in degenerative and psychiatric disorders.
  • Sasaki Makoto, Shibata Eri, Kudo Kohsuke, Tohyama Koujiro
    CLINICAL NEURORADIOLOGY 18 (3) 147 - 153 1869-1439 2008/08 [Refereed][Not invited]
     
    The basics and the technique of magnetic resonance imaging (MRI) for visualizing the neuromelanin present in dopaminergic and noradrenergic nuclei in the substantia nigra pars compacta (SNc) and locus caeruleus (LC) are introduced. Neuromelanin, a black pigment produced during catecholamine synthesis, has paramagnetic T1-shortening effects. Conventional MRI techniques fail to depict the contrast generated by neuromelanin, but neuromelanin-sensitive T1-weighted fast spin echo technique at 3 T allows the direct visualization of the SNc and LC as hyperintense areas. In Parkinson's disease, neuromelanin-related signals from the SNc and LC are diminished, suggesting neuronal degeneration in both the nuclei. In depression and schizophrenia, signals from the LC are reduced while those from the SNc are augmented, suggesting monoamine and dopamine hypotheses, respectively. Neuromelanin-sensitive MRI is a promising technique to elucidate the pathologic or functional changes in the catecholamine neurons of the brain stem that occur in degenerative and psychiatric diseases.
  • Jiani Hu, Yingjian Yu, Csaba Juhasz, Zhifeng Kou, Yang Xuan, Zahid Latif, Kohsuke Kudo, Harry T. Chugani, E. Mark Haacke
    JOURNAL OF MAGNETIC RESONANCE IMAGING 28 (2) 300 - 307 1053-1807 2008/08 [Refereed][Not invited]
     
    Purpose: To evaluate the efficacy of susceptibility weighted imaging (SWI) in comparison to standard Tl weighted postgadolinium contrast (T1-Gd) MRI in patients with SturgeWeber Syndrome (SWS). Materials and Methods: Twelve children (mean age, 5.6 years) with the diagnosis of SWS and unilateral hemispheric involvement were recruited prospectively and examined with high resolution three dimensional SWI and conventional TI-Gd. Both SWI and TI-Gd images were evaluated using a four-grade scoring system according to six types of imaging findings (enlargement of transmedullary veins, periventricular veins, and choroid plexus, as well as leptomeningeal abnormality, cortical gyriform abnormality, and gray matter/white matter junctional abnormality). The scores of SWI versus T1-Gd images were then compared for each type of abnormality. Results: SWI was superior to T1-Gd in identifying the enlarged transmedullary veins (P = 0.0020), abnormal periventricular veins (P = 0.0078), cortical gyriform abnormalities (P = 0.0020), and gray matter/white matter junction abnormalities (P = 0.0078). Conversely, TI-Gd was better than SWI in identifying enlarged choroid plexus (P = 0.0050) and leptomeningeal abnormalities (P = 0.0050). Conclusion: SWI can provide useful and unique information complementary to conventional contrast enhanced TI weighted MRI for characterizing SWS. Therefore, SWI should be integrated into routine clinical MRI protocols for suspected SWS.
  • Saito N, Kudo K, Sasaki T, Uesugi M, Koshino K, Miyamoto M, Suzuki S
    Radiological physics and technology 1 (1) 62 - 74 1865-0333 2008/01 [Refereed][Not invited]
     
    X-ray computed tomographic perfusion (CTP) imaging, a rapid method for measuring cerebral blood flow (CBF), is an effective modality for assessment of the severity and extent of brain tissue ischemia. Low-dose scanning has been required for CTP imaging for reducing the radiation exposure to patients, because the same plane is scanned repeatedly. Low-dose CTP imaging, however, results in substantial statistical noise in the images, which may negatively impact the accuracy of CBF values. Because CBF values are calculated from the set of CTP images, it is important to reduce the statistical noise in raw CTP images to make the values reliable. Noise reduction must be performed without blurring of vessel structures, because such blurring will overestimate CBF values. For this purpose, two-dimensional nonlinear diffusion filtering (NLDF) was introduced. It was applied to CTP images of a CTP phantom for evaluating the accuracy of CBF values in low-dose CTP and to clinical low-dose CTP images for determining its effectiveness in actual CTP examinations. NLDF successfully reduced the statistical noise in the CTP images while preserving the sharp edges. This feature generated CBF values close to the reference value, producing reliable CBF maps from low-dose CT perfusion images. The CBF maps obtained with NLDF were comparable to or better than those obtained by other, commercial CTP software programs. The use of NLDF was thus effective for manipulation of low-dose CT perfusion images.
  • Satoshi Terae, Daisuke Yoshida, Kohsuke Kudo, Khin Khin Tha, Masaharu Fujino, Kazuo Miyasaka
    Journal of magnetic resonance imaging : JMRI 25 (3) 479 - 87 1053-1807 2007/03 [Refereed][Not invited]
     
    PURPOSE: To assess whether the use of postcontrast fluid-attenuated inversion recovery (FLAIR) imaging in combination with pre- and postcontrast magnetization transfer (MT) T1-weighted imaging (T1WI) can increase diagnostic confidence in the evaluation of brain metastases. MATERIALS AND METHODS: Brain MR images from 41 patients with suspected brain metastases were reviewed. Two radiologists viewed pre- and postcontrast MT-T1W images for the presence of metastatic tumors and rated the possible enhanced lesions using a five-point confidence scale (session 1). The postcontrast FLAIR images were then viewed together with pre- and postcontrast MT-T1W images, and the presence of metastasis was rated again (session 2). RESULTS: A total of 240 possible enhanced lesions were detected in session 1. Judging by follow-up MR examinations, 196 were considered to be nonmetastatic findings and 44 were determined to be metastasis. In session 2 the confidence rating for nonmetastasis increased significantly in the subset of nonmetastatic findings (P < 0.001), and the confidence rating for metastasis increased significantly in the subset of metastases (P < 0.05). CONCLUSION: The addition of postcontrast FLAIR imaging to pre- and postcontrast MT-T1WI improves diagnostic confidence in evaluation of brain metastases.
  • Yuri Yoshida, Satoshi Terae, Kohsuke Kudo, Khin Khin Tha, Masahiro Imamura, Kazuo Miyasaka
    JOURNAL OF COMPUTER ASSISTED TOMOGRAPHY 30 (6) 980 - 982 0363-8715 2006/11 [Refereed][Not invited]
     
    A case of brain stem capillary telangiectasia diagnosed by susceptibility-weighted imaging is reported. A small enhancing pontine lesion was found on postcontrast T1 -weighted MR images in a 56-year-old woman with human T-cell leukemia virus type I infection. Imaging diagnosis was difficult with conventional MR imaging because the lesion did not show characteristic signal loss on conventional gradient-echo images. SWI was useful for imaging diagnosis as it demonstrated marked signal loss of the lesion.
  • Toshiya Osanai, Satoshi Kuroda, Tatsuya Ishikawa, Kohsuke Kudo, Satoshi Terae, Masanori Isobe, Yoshinobu Iwasaki
    No shinkei geka. Neurological surgery 34 (4) 403 - 7 0301-2603 2006/04 [Refereed][Not invited]
     
    The authors report a 6-year-old girl presented with headache and transient ischemic attack due to moyamoya disease. MR angiography (MRA) revealed that her symptoms were closely related to reversible deterioration of stenosis in the left middle cerebral artery (MCA). Deterioration of stenosis led to a decreased flow signal in the distal branches of the left MCA. MRA could also detect reversible stenotic changes in the right MCA, although she did not develop any neurological symptom. Although precise mechanism of reversible MR angiographic findings is still unknown, the phenomenon may play an important role in disease progression in pediatric patients with moyamoya disease.
  • Shunsuke Onodera, Satoshi Terae, Kohsuke Kudo, Khin Khin Tha, Kazuo Miyasaka, Kazutoshi Hida, Yoshinobu Iwasaki, Satoshi Ota
    European Journal of Radiology Extra 57 (2) 41 - 45 1571-4675 2006/02 [Refereed][Not invited]
  • SASAKI M
    International Congress Series 1290 30 - 36 2006 [Refereed][Not invited]
  • Hongying Zuo, Shigehito Suzuki, Minoru Sotoda, Masahito Uesugi, Kosuke Kudo
    Igaku butsuri : Nihon Igaku Butsuri Gakkai kikanshi = Japanese journal of medical physics : an official journal of Japan Society of Medical Physics 26 (2) 65 - 74 1345-5354 2006 [Refereed][Not invited]
     
    Visualization techniques for magnetic resonance (MR) angiographic images are generally based on the projection ray concept; for example, maximum intensity projection (MIP) and volume rendering (VR). A new technique based on a different concept from projection rays is explored in this study: three-dimensional (3-D) discrete wavelet transforms are used for visualizing cerebral vessels in the MR angiographic image. This technique successfully visualizes cerebral vessels and represents the spatial relationship between the cerebral vessels, as in the case of VR. The proposed technique is, thus, indicated to be promising for visualizing cerebral vessels in 3-D MR angiographic images.
  • KK Tha, S Terae, K Kudo, T Yamamoto, S Hamada, A Ogata, H Sasaki, K Miyasaka
    JOURNAL OF COMPUTER ASSISTED TOMOGRAPHY 30 (1) 126 - 130 0363-8715 2006/01 [Refereed][Not invited]
     
    The authors report a case of subacute sclerosing pariencephalitis in which the diagnosis was suggested by high b-value diffusion-weighted imaging (DWI) findings. The signal abnormalities were located asymmetrically at bilateral cerebral corticosubcortical regions. High b-value DWI showed these signal abnormalities as marked hyperintensity with decreased apparent diffusion coefficient values. The signal abnormalities were difficult to identify on other magnetic resonance imaging sequences, including routine DWI. High b-value DWI could be valuable for earlier detection of subacute sclerosing panencephalitis.
  • Tatsuya Ishikawa, Satoshi Kuroda, Naoki Nakayama, Satoshi Terae, Kousuke Kudou, Yoshinobu Iwasaki
    Neurologia medico-chirurgica 45 (10) 495 - 500 0470-8105 2005/10 [Refereed][Not invited]
     
    Basal moyamoya vessels are a potential source of hemorrhage in patients with moyamoya disease, but the etiology remains unclear. Symptomatic hemorrhage resulting from long-standing hemodynamic effects on pathologically dilated, fragile moyamoya vessels may be preceded by asymptomatic microbleeding in adult moyamoya disease patients, regardless of hemorrhagic or ischemic onset. T2*-weighted magnetic resonance (MR) imaging was used to investigate the presence of microbleeds in 27 adult patients with angiographically confirmed moyamoya disease, 21 females and six males aged 18-70 years (mean 40.8 +/- 15.7 years). Clinical diagnosis was intracranial bleeding in six patients, transient ischemic attack or cerebral infarction in 18, and asymptomatic in three. Asymptomatic microbleeds were detected in four of the 27 patients, two of six who initially presented with hemorrhagic events and two of 18 with ischemic onset. These microbleeds were located in the paraventricular white matter, temporal subcortex, and basal ganglia. The presence of microbleeds had no correlation with either patient age or duration from disease onset or diagnosis of disease. A large cohort study is needed to explore the significance of asymptomatic microbleeds in moyamoya disease.
  • Hidefumi Aoyama, Hiroki Shirato, Norio Katoh, Kohsuke Kudo, Takeshi Asano, Satoshi Kuroda, Tatsuya Ishikawa, Kazuo Miyasaka
    International journal of radiation oncology, biology, physics 62 (4) 1232 - 8 0360-3016 2005/07/15 [Refereed][Not invited]
     
    PURPOSE: To investigate the discrepancy between the arteriovenous malformations seen on magnetic resonance angiography (MRA) and on stereotactic digital subtracted angiography (DSA). METHODS AND MATERIALS: The target volume on stereotactic DSA (V(DSA)) and the target volume on MRA (V(MRA)) were separately delineated in 28 intracranial arteriovenous malformations. The coordinates of the center and the outer edges of V(DSA) and V(MRA) were calculated and used for the analyses. RESULTS: The standard deviations (mean value) of the displacement of centers of V(MRA) from V(DSA) were 2.67 mm (-1.82 mm) in the left-right direction, 3.23 mm (-0.08 mm) in the anterior-posterior direction, and 2.16 mm (0.91 mm) in the craniocaudal direction. V(MRA) covered less than 80% of V(DSA) in any dimensions in 9 cases (32%), although no significant difference was seen in the target volume between each method, with a mean value of 11.9 cc for V(DSA) and 12.3 cc for V(MRA) (p = 0.948). CONCLUSION: The shift of centers between each modality is not negligible. Considering no significant difference between V(DSA) and V(MRA), but inadequate coverage of the V(DSA) by V(MRA), it is reasonable to consider that the target on MRA might include the feeding artery and draining vein and possibly miss a portion of the nidus.
  • Emiko Kaito, Satoshi Terae, Ryoji Kobayashi, Kohsuke Kudo, Khin Khin Tha, Kazuo Miyasaka
    Pediatric radiology 35 (7) 722 - 7 0301-0449 2005/07 [Refereed][Not invited]
     
    We report on a child with B-cell lymphoma who developed hypertension and reversible posterior leukoencephalopathy syndrome (RPLS) after chemotherapy conducted during recovery from tumor lysis syndrome. After recovery from RPLS, the patient received further combination chemotherapy without recurrence of the neurological signs or symptoms suggestive of RPLS. Many etiological factors have been reported in the development of RPLS; however, little attention has been paid to tumor lysis syndrome as a contributory factor for RPLS. Tumor lysis syndrome can precipitate the development of RPLS in patients with hematological malignancies who are undergoing chemotherapy. Knowledge and awareness would help facilitate immediate management such as normalization of blood pressure and temporary cessation of chemotherapy, helping to avoid irreversible brain damage.
  • KK Tha, S Terae, T Yamamoto, K Kudo, C Takahashi, M Oka, S Uegaki, K Miyasaka
    AMERICAN JOURNAL OF NEURORADIOLOGY 26 (6) 1487 - 1497 0195-6108 2005/06 [Refereed][Not invited]
     
    BACKGROUND AND PURPOSE: Early and accurate detection of global cerebral anoxia is important for determination of prognosis and further management. We evaluated whether accuracy in early detection of global cerebral anoxia was improved by high-b-value diffusion-weighted imaging (DWI) with long echo time (TE).METHODS: Routine DWI (b = 1000 s/mm(2); TE = 139 ms), high-b-value DWI (b = 3000 s/mm(2); TE = 190 ms), T2-weighted imaging (T2WI), and fluid-attenuated inversion recovery (FLAIR) imaging were acquired in six patients who experienced cardiopulmonary arrest within 24 hours and six volunteers. Region of interest-based analysis was performed. Regions of interest of patients showing significant decrease in apparent diffusion coefficient (ADC)3 values than volunteers were considered abnormal. Three neuroradiologists independently assessed images of the patients for conspicuity of hyperintensity within regions of interest. Receiver operating characteristic (ROC) analysis was performed, and the area under the curve (Az) was compared among sequences and observers. Average contrast and contrast-to-noise ratios between abnormal regions of interest and regions of interest of normal surrounding parenchyma were calculated.RESULTS: For all observers, high-b-value DWIs achieved the largest Az, and FLAIR imaging the lowest Az. Az of routine DWI and T2WI were between these values. High-b-value DWI and FLAIR imaging showed no significant interobserver variation in Az, whereas routine DWI and T2WI did. High-b-value DWI also achieved the largest contrast and contrast-to-noise ratios.CONCLUSION. High-b-value DWI with long TE improved accuracy in early detection of global cerebral anoxia. Application of the sequence would facilitate early diagnosis.
  • Kudo Kohsuke
    Jpn. J. Stroke The Japan Stroke Society 27 (4) 568 - 571 0912-0726 2005 
    CT and MR perfusion imaging are useful tools in evaluation of regional blood flow in acute ischemic stroke. However, quantitative results show fluctuations, because scan protocol and analysis method are not standardized. In addition, inadequate settings of scan parameters can induce unnecessary radiation exposure in CT perfusion. Therefore, standardization of scan protocol, analysis methods, and evaluation methods are needed.
    It is important to standardize scan parameters, in order to assure safety of the patients. Standardization of scan parameters and analysis methods is also important to minimize variations of quantitative values. In order to evaluate the degree of ischemia correctly, defining a universal index for the ischemic lesion, such as DWI-PWI mismatch, is required.
    In summary, the goal of the standardization is to assure the safety of patients, to ensure the reliability of results, and to establish universal evaluation methods. In Japan, standardization of perfusion imaging, as well as other stroke imaging, is being carried out by ASIST-Japan (Acute Stroke Imaging Standardization).
  • 増田 香織, 笹木 工, 熊谷 まなみ, 山下 道明, 工藤 與亮
    日本放射線技術学会雑誌 公益社団法人 日本放射線技術学会 61 (9) 1297 - 1297 2005
  • 笹木 工, 増田 香織, 熊谷 まなみ, 山下 道明, 工藤 與亮
    日本放射線技術学会雑誌 公益社団法人 日本放射線技術学会 61 (9) 1297 - 1297 2005
  • Kohsuke Kudo, Satoshi Terae, Aki Ishii, Tokuhiko Omatsu, Takeshi Asano, Khin Khin Tha, Kazuo Miyasaka
    AJNR. American journal of neuroradiology 25 (4) 551 - 7 0195-6108 2004/04 [Refereed][Not invited]
     
    BACKGROUND AND PURPOSE: Blood flow of the internal jugular vein and intracranial venous sinuses is affected by respiratory state. The purpose of this study was to clarify the changes in flow velocity and direction and signal intensities of sigmoid sinuses on phase-contrast (PC) MR images obtained with regular breathing and with deep inspiratory breath holding. METHODS: One hundred seven subjects without venous sinus abnormality were studied. Coronal 2D PC MR venography and axial 2D PC images with peripheral pulse gating were acquired with a 1.5-T MR unit, during regular breathing and deep inspiratory breath holding. The signal intensity changes of bilateral sigmoid sinuses on MR venograms and the changes of flow velocity and direction on the axial 2D PC images were analyzed. RESULTS: Breath holding decreased signal intensities of the right and left sigmoid sinuses on MR venograms in 57 (53.3%) and 36 (33.6%) subjects, respectively. Increased signal intensity was observed in 12 (11.2%) and 33 (30.8%) subjects, respectively. In the flow analysis, retrograde flow was detected at the left sigmoid sinus in four subjects (3.7%) during regular breathing, which was normalized by breath holding. Flow velocities of the right and left sigmoid sinuses decreased during breath holding in 92 (86.0%) and 70 (65.4%) subjects, and increased in 15 (14.0%) and 37 (34.6%) subjects, respectively. CONCLUSION: The signal intensities of sigmoid sinuses were affected by breath holding in about 2/3 of the subjects. Breath-holding maneuver can be used to increase blood flow and signal intensities of dural venous sinuses on PC MR venograms.
  • 笹木 工, 山下 道明, 石坂 欣也, 工藤 與亮
    日本放射線技術学会雑誌 公益社団法人 日本放射線技術学会 60 (9) 1206 - 1206 2004
  • S Terae, K Kudo, T Asano, S Ushikoshi, K Hida, Y Iwasaki, K Miyasaka
    CLINICAL IMAGING 28 (1) 23 - 27 0899-7071 2004/01 [Refereed][Not invited]
     
    We performed intravenous CT angiography using multidetector-row helical computed tomography (MDCT) in a 63-year-old man with spinal arteriovenous malformation (AVM). The CT angiography demonstrated feeding arteries, varix-like structure, draining veins and their relationship to the spinal cord. Although selective angiography is essential in planning treatment for spinal AVMs as well as in establishing the diagnosis of the disease, CT angiography can be a good supplementary technique for visualizing precise location of abnormal vessels in a certain case of spinal AVM. (C) 2004 Elsevier Inc. All rights reserved.
  • M Oka, S Terae, R Kobayashi, Y Sawamura, K Kudoh, K K Tha, M Yoshida, M Kaneda, Y Suzuki, K Miyasaka
    Neuroradiology 45 (7) 493 - 7 0028-3940 2003/07 [Refereed][Not invited]
     
    We report two fatal cases of methotrexate (MTX)-induced disseminated necrotising leukoencephalopathy (DNL) in which MRI was repeated from the onset. Initial T2-weighted images showed multiple areas of high signal, mainly in deep cerebral white matter, which on follow-up, spread and coalesced to involve the entire white matter. Small irregular low-signal foci on T2-weighted images were seen within the high-signal lesions. Multiple areas of contrast enhancement corresponded to these low-signal foci. The condition of both patients deteriorated and they died. We compared their MRI findings with those of seven patients with mild MTX-related leukoencephalopathy, six of whom were asymptomatic; one had transient neurological symptoms. They showed no contrast enhancement, but rather mild-to-moderate diffuse high signal in deep white matter, which later disappeared. These findings suggest that multiple low-signal foci on T2-weighted images with contrast enhancement may be characteristic of DNL, and that contrast-enhanced imaging is useful to differentiate this condition from mild leukoencephalopathy.
  • Kohsuke Kudo, Satoshi Terae, Chietsugu Katoh, Masaki Oka, Tohru Shiga, Nagara Tamaki, Kazuo Miyasaka
    AJNR. American journal of neuroradiology 24 (3) 419 - 26 0195-6108 2003/03 [Refereed][Not invited]
     
    BACKGROUND AND PURPOSE: Blood vessels are usually conspicuous on dynamic CT perfusion images. The presence of large vessels may lead to overestimation of the quantitative value of cerebral blood flow (CBF). We evaluated the efficacy of the vascular-pixel elimination (VPE) method in quantitative CT perfusion imaging, in comparison with positron emission tomography (PET). METHODS: Five healthy volunteers underwent CT perfusion and PET studies. A four-channel multi-detector row CT scanner was used. Dynamic cine scanning was performed after bolus injection of an intravenous contrast agent. CT-CBF was calculated by the central volume principle and deconvolution method. PET was performed after infusion of (15)O-labeled water. PET-CBF was calculated by using a nonlinear least squares method. Average CBF values of the whole section, gray matter, and white matter with both CT and PET were compared after image registration. The comparison was performed with and without VPE. In the VPE method, the vascular pixels were defined by the cerebral blood volume value of the pixel. The threshold of VPE was changed from 5 to 20 mL/100 g. Pixel-by-pixel correlation between CT-CBF and PET-CBF and linear regression analysis were also performed. RESULTS: Without VPE, CT-CBF was overestimated in all subjects. As the VPE threshold decreased, CT-CBF decreased and the correlation coefficient increased. The best correlation was observed at a VPE threshold of 8 mL/100 g in four of the five subjects. Average CT-CBF values, without VPE, of the whole section, gray matter, and white matter were 59.01, 66.73, and 42.53 mL/100 g/min, respectively. With VPE (threshold, 8 mL/100 g), average CT-CBF values of the whole section, gray matter, and white matter were 45.56, 52.75, and 30.38, respectively. The corresponding PET-CBF values were 46.86, 50.89, and 38.20 mL/100 g/min, respectively. CONCLUSION: Vascular pixels should be excluded from the calculation of CT-CBF to avoid overestimation of the CBF values. If vascular pixels are excluded, CBF calculation with CT perfusion imaging is considerably accurate.
  • Kohsuke Kudo, Satoshi Terae, Takeshi Asano, Masaki Oka, Kenshi Kaneko, Satoshi Ushikoshi, Kazuo Miyasaka
    AJNR. American journal of neuroradiology 24 (1) 13 - 7 0195-6108 2003/01 [Refereed][Not invited]
     
    BACKGROUND AND PURPOSE: Our purpose was to evaluate the visualization of the artery of Adamkiewicz (AKA) and the anterior spinal artery (ASA) by using multi-detector row CT. Preoperative detection of the AKA and ASA is important for prevention of ischemic complications of thoracoabdominal aortic surgery. METHODS: Data from contrast-enhanced CT of the abdomen of 19 consecutive patients with known or suspected liver disease were evaluated. The scanning range was set from the level of the diaphragm to the lower edge of the liver. After bolus injection of contrast material (100 mL of iohexol, 350 mgI/mL, 5 mL/s), arterial phase scans were obtained by using a four-channel multi-detector row CT scanner. The scanning parameters included a detector row configuration of 4 x 2 mm, a pitch of 5:1, a gantry rotation speed of 0.5 s, 120 kVp, and 150 mAs. Arterial phase coronal multiplanar reconstruction scans obtained parallel to the spinal cord were evaluated by two neuroradiologists. The detectability of ASA and AKA was analyzed. RESULTS: The AKA was visualized on the scans of 13 of 19 patients (68%). The segmental level of AKA origin ranged from T10 to L2. The AKA originated from the left side in nine patients (69%) and the right side in four patients (31%). The ASA was visualized on the scans of all patients (100%). For 16 of the 19 patients, the ASA was detected in its full length from the cranial edge of the scan range. However, the ascending branch of the ASA distal to the junction of the AKA was not detected for the remaining three patients. CONCLUSION: The AKA and ASA can be visualized by using multi-detector row CT with the use of IV administered contrast material. Multi-detector row CT could be a useful tool in the evaluation of spinal vascular structures.
  • K K Tha, S Terae, M Sugiura, T Nishioka, M Oka, K Kudoh, K Kaneko, K Miyasaka
    Acta neurologica Scandinavica 106 (6) 379 - 86 0001-6314 2002/12 [Refereed][Not invited]
     
    We report a case of 5-fluorouracil (5-FU)-induced leukoencephalopathy in which magnetic resonance imaging (MRI) of the brain, including diffusion-weighted imaging (DWI), was performed serially. The initial T2-weighted and FLAIR images showed diffuse mild hyperintensity in bilateral deep cerebral white matter and corpus callosum, which on T1WI appeared as non-enhanced faint hypointensity. Isotropic DWI disclosed the abnormality as well-conspicuous diffuse hyperintensity with decreased ADC. Serial studies revealed that majority of the abnormal signal intensity on these sequences resolved, and the decreased ADC values approached normal. Some hyperintensity remained in the deep cerebral white matter and the splenium, but no further significant ADC change after normalization was noted. Measurement of ADC along the three orthogonal directions showed the presence of directional dependence of diffusion throughout the length of study. These findings suggest that early stage of 5-FU-induced leukoencephalopathy is associated with reversible restricted diffusion and preservation of anisotropy. Diffusion-weighted imaging may be useful for the diagnosis.
  • 笹木 工, 山下 道明, 孫田 恵一, 寺江 聡, 工藤 與亮, 加藤 千恵次
    日本放射線技術学会雑誌 公益社団法人 日本放射線技術学会 58 (9) 1146 - 1146 2002
  • M Oka, S Terae, R Kobayashi, K Kudoh, B C Chu, K Kaneko, M Yoshida, M Kaneda, Y Suzuki, K Miyasaka
    Acta neurologica Scandinavica 104 (3) 178 - 81 0001-6314 2001/09 [Refereed][Not invited]
     
    We report a case of acute Wernicke encephalopathy (WE) in which apparent diffusion coefficient maps showed areas of increased diffusion in the bilateral medial thalami that corresponded to the hyperintense lesions on T2-weighted imaging. The hyperintense lesions on T2-weighted imaging disappeared with full recovery from symptoms. These findings suggest that the hyperintense lesions of the acute changes of WE include reversible vasogenic edema and are not caused by acute ischemia.
  • 遠隔画像診断に関する検討
    南部 敏和, 工藤 與亮, 立石 宇貴秀, 宮坂 和男, 尾松 徳彦, 井上 幸夫
    日本医学放射線学会雑誌 (公社)日本医学放射線学会 61 (6) 314 - 314 0048-0428 2001/05
  • Teleradiologyの実践経験と発展性に関する検討
    南部 敏和, 工藤 與亮, 尾松 徳彦, 立石 宇貴秀, 宮坂 和男
    日本医学放射線学会雑誌 (公社)日本医学放射線学会 61 (2) S244 - S244 0048-0428 2001/02
  • S Terae, K Miyasaka, K Kudoh, T Nambu, T Shimizu, K Kaneko, H Yoshikawa, R Kishimoto, T Omatsu, N Fujita
    Journal of digital imaging 13 (4) 178 - 90 0897-1889 2000/11 [Refereed][Not invited]
     
    The purpose of this report is to assess clinically acceptable compression ratios on the detection of brain lesions at magnetic resonance imaging (MRI). Four consecutive T2-weighted and the corresponding T1-weighted images obtained in 20 patients were studied for 109 anatomic sites including 50 with lesions and 59 without lesions. The images were obtained on a 1.5-T MR unit with a pixel size of 0.9 to 1.2 x 0.47 mm and a section thickness of 5 mm. The image data were compressed by wavelet-based algorithm at ratios of 20:1, 40:1, and 60:1. Three radiologists reviewed these images on an interactive workstation and rated the presence or absence of a lesion with a 50 point scale for each anatomic site. The authors also evaluated the influence of pixel size on the quality of image compression. At receiver operating characteristic (ROC) analysis, no statistically significant difference was detected at a compression ratio of 20:1. A significant difference was observed with 40:1 compressed images for one reader (P = .023), and with 60:1 for all readers (P = .001 to .012). A root mean squared error (RMSE) was higher in 0.94- x 0.94-mm pixel size images than in 0.94- x 0.47-mm pixel size images at any compression ratio, indicating compression tolerance is lower for the larger pixel size images. The RMSE, subjective image quality, and error images of 10:1 compressed 0.94- x 0.94-mm pixel size images were comparable with those of 20:1 compressed 0.94- x 0.47-mm pixel size images. Wavelet compression can be acceptable clinically at ratios as high as 20:1 for brain MR images when a pixel size at image acquisition is around 1.0 x 0.5 mm, and as high as 10:1 for those with a pixel size around 1.0 x 1.0 mm.
  • H Shirato, S Shimizu, T Kunieda, K Kitamura, M van Herk, K Kagei, T Nishioka, S Hashimoto, K Fujita, H Aoyama, K Tsuchiya, K Kudo, K Miyasaka
    International journal of radiation oncology, biology, physics 48 (4) 1187 - 95 0360-3016 2000/11/01 [Refereed][Not invited]
     
    PURPOSE: To reduce uncertainty due to setup error and organ motion during radiotherapy of tumors in or near the lung, by means of real-time tumor tracking and gating of a linear accelerator. METHODS AND MATERIALS: The real-time tumor-tracking system consists of four sets of diagnostic X-ray television systems (two of which offer an unobstructed view of the patient at any time), an image processor unit, a gating control unit, and an image display unit. The system recognizes the position of a 2.0-mm gold marker in the human body 30 times per second using two X-ray television systems. The marker is inserted in or near the tumor using image guided implantation. The linear accelerator is gated to irradiate the tumor only when the marker is within a given tolerance from its planned coordinates relative to the isocenter. The accuracy of the system and the additional dose due to the diagnostic X-ray were examined in a phantom, and the geometric performance of the system was evaluated in 4 patients. RESULTS: The phantom experiment demonstrated that the geometric accuracy of the tumor-tracking system is better than 1.5 mm for moving targets up to a speed of 40 mm/s. The dose due to the diagnostic X-ray monitoring ranged from 0.01% to 1% of the target dose for a 2.0-Gy irradiation of a chest phantom. In 4 patients with lung cancer, the range of the coordinates of the tumor marker during irradiation was 2.5-5.3 mm, which would have been 9.6-38.4 mm without tracking. CONCLUSION: We successfully implemented and applied a tumor-tracking and gating system. The system significantly improves the accuracy of irradiation of targets in motion at the expense of an acceptable amount of diagnostic X-ray exposure.

Conference Activities & Talks

  • Atsushi Tada, Toshiyuki Nagai, Yoshiya Kato, Noriko Oyama-Manabe, Satonori Tsuneta, Michikazu Nakai, Yutaro Yasui, Sho Kazui, Yuki Takahashi, Kohei Saiin, Seiichiro Naito, Sakae Takenaka, Yoshifumi Mizuguchi, Yuta Kobayashi, Suguru Ishizaka, Kazunori Omote, Takuma Sato, Takao Konishi, Kiwamu Kamiya, Kohsuke Kudo, Toshihisa Anzai
    The American journal of cardiology  2023/06 
    Several liver fibrotic markers are associated with prognosis in patients with heart failure (HF). However, the optimal markers for outcome prediction remain unclear. This study aimed to simultaneously investigate the prognostic value of liver fibrotic markers and the associations between these markers and clinical parameters in patients with HF without organic liver disease. We prospectively examined 211 consecutive patients with chronic HF between April 2018 and August 2021, excluding those with organic liver disease, using liver magnetic resonance imaging and ultrasound. A total of 7 representative liver fibrotic markers were measured in all patients. The primary outcome of interest was the composite of all-cause death and hospitalization for worsening HF. During a median follow-up period of 747 (interquartile range 465 to 1,042) days, the primary outcome occurred in 45 patients. Patients with higher hyaluronic acid and type III procollagen N-terminal peptide (P-III-P) levels showed a significantly higher incidence of the primary outcome than those without (p <0.001 and p = 0.005, respectively). The multivariable Cox regression analysis revealed that hyaluronic acid and P-III-P levels were independently associated with the risk of adverse events (hazard ratio 1.84, 95% confidence interval 1.18 to 2.87 and hazard ratio 2.89, 95% confidence interval 1.32 to 6.34, respectively) even after adjustment for a mortality prediction model, whereas the other 5 markers were not associated with the primary outcome. In conclusion, among the representative liver fibrotic markers, hyaluronic acid and P-III-P might be the optimal markers for outcome prediction in patients with HF.

MISC

Industrial Property Rights

  • 医用画像処理装置及び医用画像の処理法 「CT Perfusionにおける血管除去法と画像」
    2004-108291
  • Vascular Pixel Elimination in CT Perfusion
    2004-108291

Awards & Honors

  • 2019/09 日本磁気共鳴医学会 Excellent Paper Award
     Indirect Proton MR Imaging and Kinetic Analysis of 17O-Labeled Water Tracer in the Brain 
    受賞者: KUDO Kohsuke
  • 2018/04 Japanese Society of Radiology JJR Excellent Reviewer Award in 2017
     
    受賞者: KUDO Kohsuke
  • 2012/09 Japanese Society of Magnetic Resonance Imaging Academic Encouragement Award
     定量的磁化率マップ(QSM)を利用したOEF画像:主幹動脈病変患者におけるPETとの比較 
    受賞者: KUDO Kohsuke
  • 2010/02 Japanese Society of Neuroradiology Silver Award
     デジタルファントムを用いたCT 灌流画像解析ソフトの精度検証 
    受賞者: KUDO Kohsuke
  • 2010/02 北海道大学医学部同窓会 Furate Research Encouragement Award
     CT灌流画像を用いた脳血流解析に関する研究 
    受賞者: 工藤 與亮
  • 2008/09 Japanese Society of Magnetic Resonance Imaging Academic Encouragement Award
     SWIを用いた定量的脳血流マップの開発 
    受賞者: KUDO Kohsuke
  • 2008/04 Japanese Society of Radiology Cyper Rad Award
     Perfusion Mismatch Analyzer (PMA):自動化・標準化された灌流画像解析ソフトウェア 
    受賞者: KUDO Kohsuke
  • 2006/04 Japanese Society of Radiology Bronze Award
     Standardization of CT and MR Perfusion Analysis 
    受賞者: KUDO Kohsuke
  • 2006/03 World Neuroradiology Symposium Travel Award
     Standardization of Analysis Methods in CT and MR Perfusion Imaging 
    受賞者: KUDO Kohsuke
  • 2005/10 北海道脳PET・SPECT研究会 Excellent Paper Award
     CT Perfusionの定量性に関する検討-PETとの比較- 
    受賞者: KUDO Kohsuke
  • 2005/02 Japanese Society of Neuroradiology Excellent Paper Award
     脳血流ファントムを用いた低線量CT Perfusionの限界の検討 
    受賞者: KUDO Kohsuke
  • 2004/02 Radiological Society of North America Certificate of Merit
     Optimization of Scan Protocol and Analyzing Method for Low Dose CT Perfusion: How to Reduce Radiation Dose in CT Perfusion Study 
    受賞者: KUDO Kohsuke
  • 2004/02 Japanese Society of Neuroradiology Kato Award
     Quantitative cerebral blood flow measurement with dynamic perfusion CT using the vascular-pixel elimination method: comparison with H2(15)O positron emission tomography 
    受賞者: KUDO Kohsuke
  • 2003/06 北海道大学放射線医学講座同門会 Wakabayashi Award
     Quantitative cerebral blood flow measurement with dynamic perfusion CT using the vascular-pixel elimination method: comparison with H2(15)O positron emission tomography 
    受賞者: KUDO Kohsuke
  • 2003/02 Japanese Society of Neuroradiology Excellent Paper Award
     頭蓋内静脈洞におけるMRVと血流測定:息止めによる血流速度および方向の生理的変動について 
    受賞者: KUDO Kohsuke
  • 2001/02 Japanese Society of Neuroradiology Excellent Paper Award
     Multi-Detector Row CTを用いたAdamkiewicz動脈および前脊髄動脈の描出 
    受賞者: KUDO Kohsuke
  • 1998/12 Radiological Society of North America Certificate of Merit
     Effect of Compression Parameters in Wavelet Method: Analysis of Image Quality and Compression Errors in CT and MR Images 
    受賞者: KUDO Kohsuke
  • 1997/12 Radiological Society of North America Certificate of Merit
     ROC Analysis of Digital Image Data Compression: Clinically Acceptable Compression Ratio of CT and MR Images of the Brain 
    受賞者: KUDO Kohsuke

Research Grants & Projects

  • Japan Society for the Promotion of Science:Grants-in-Aid for Scientific Research
    Date (from‐to) : 2023/04 -2026/03 
    Author : 平井 俊範, 工藤 與亮, 菰原 義弘, 上谷 浩之, 武笠 晃丈
  • Japan Society for the Promotion of Science:Grants-in-Aid for Scientific Research
    Date (from‐to) : 2021/04 -2024/03 
    Author : 曽山 武士, 工藤 與亮, 平田 健司
     
    2021年度は、当初予定していたフュージョンビューワーの改良やデジタルファントムを用いた照射予想域の表示に留まらず、光量分布集計機能を持つ「高精度光免疫治療システム」の開発に着手した。また、このシステムの基礎的検討を行うために、①臨床解剖に即した構造を有し、②穿刺可能、③開口可能、④CTによる腫瘍・穿刺位置の客観的評価が可能な頭頸部ファントムを開発し、7月3日の第6回 日本穿刺ドレナージ研究会と11月26日の第36回 道東画像診断・治療ケア研究会で報告した。 光免疫療法のためのナビゲーションシステムを臨床で使用する際に、コーンビームCT撮像時にアーチファクトを発生しうる金属製のデバイスが問題であった。そこで、2021年度にCAD でデザインし3Dプリンターで印刷した非金属製開口器と非金属製ガイドニードルを開発し、11月26日の第36回 かしわ画像研究会で報告した。 また、歯肉癌を想定した光免疫療法のためのナビゲーションデバイスとして、2021年度にインプラントの際にドリルで下顎骨に穴を空ける技術を応用し、光ファイバーの穿刺を計画通りに行うことのできる穿刺ガイドプレートを開発し、11月26日の第36回 かしわ画像研究会で報告した。 この他、2021年度は柔軟な舌を有する頭頸部模型を開発し、これを用いて光免疫療法の術前画像と術中画像の非剛体画像レジストレーションの精度評価に取り組んだが、非剛体画像レジストレーションを行うとほとんど重ね合わせの誤差が発生せず、一方で原版の光免疫療法のためのナビゲーションシステムは重ね合わせが出来ないことが判明したため、これらの比較実験は行なっていない。
  • Japan Society for the Promotion of Science:Grants-in-Aid for Scientific Research
    Date (from‐to) : 2021/04 -2024/03 
    Author : 工藤 與亮, 村上 正晃, 小畠 隆行, 小牧 裕司, 杉森 博行, 坂本 直哉, 亀田 浩之, 安井 正人
     
    ①MRI撮像法開発:O-17標識水の存在によるT2値の短縮を定量的に計測してO-17濃度を定量解析するため、プリパルスを利用した高速T2 mapping法を開発して最適化を行った。異なる濃度のO-17標識水を含有した濃度ファントムを作成し、高速T2 mapping法と従来のFSE法によるT2 mapping法の精度を比較した。従来法と比較して高精度のT2値測定が可能となった。 ②正常動物・疾患モデル動物でのMRI撮像:正常マウスやラットにてO-17標識水の静脈内投与法や髄腔内投与法、頸動脈内投与法、腹腔内投与法などを確立した。静脈内投与や頸動脈内投与によって脳内の有意なMRI信号変化を確認した。水中毒モデルラットにO-17標識水を腹腔内投与してMRI撮像を行い、AQP4欠損ラットとの比較を行った。AQP4欠損によって脳内の水貯留が増加することが明らかになった。ALSモデルマウス・ラットにてO-17標識水を静脈内投与してMRI撮像を行った。野生型と比較して錐体路での水漏出が増加していることが明らかとなった。 ③同位体顕微鏡による水分子イメージング:新たに導入した多機能コーティング装置を用いて凍結下での標本作成から同位体顕微鏡によるイメージングまでの解析手順を確立した。ラット脳にO-18標識水を直接注入し、注入部位でのO-18濃度の上昇を確認した。摘出したラット肝の門脈内にO-18標識水を注入し、血管内や類洞内のO-18濃度の上昇を確認した。 ④ヒトでのMRI撮像:認知症患者を対象にしたO-17標識水の髄腔内投与研究にて、特発性正常圧水頭症患者とアルツハイマー型認知症患者で、髄腔内の水吸収速度に差があることを見出した。
  • Japan Society for the Promotion of Science:Grants-in-Aid for Scientific Research
    Date (from‐to) : 2017/04 -2020/03 
    Author : Kudo Kohsuke
     
    Theoretical equation that converts MRI signal to O-17 concentration was successfully derived from the phantom acquisition (containing different concentration of O-17 water) and signal simulation of MRI. MRI experiments of culture cells in vitro were performed, and significant signal changes were observed after administration of O-17 gas or O-17 glucose, which were then converted into O-17 water. These results suggested that oxygen and glucose metabolisms could be measured by MRI using O-17. Intrathecal administration of O-17 water in rats were also conducted and dynamic signal changes of MRI in cerebrospinal fluid spaces were visualized. Quantitative water kinetics could be analyzed using human MRI data of intrathecal administration of O-17 water.
  • 拡散・灌流・磁化率MRIの統合による多角的無侵襲脳循環代謝イメージング法の確立
    Japan Society for the Promotion of Science:Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)
    Date (from‐to) : 2017/04 -2020/03 
    Author : 佐々木 真理, 小笠原 邦昭, 工藤 與亮, 平野 照之
     
    脳循環代謝検査は脳卒中の予防や診療において重要な役割を果たしているが、ゴールドスタンダードであるPETやSPECTは、侵襲性・汎用性・即時性・経済性の点で課題が多い。そこで、MRIによる拡散・灌流・磁化率画像を統合することで、脳血流量(CBF)、血管反応性(CVR)、脳血液量(CBV)、脳酸素摂取率(OEF)などの機能画像を高精度に算出する独自の画像解析法を開発し、急性期脳梗塞や慢性脳虚血における精度検証を行うことで、PET・SPECTの代替となりうる次世代無侵襲脳循環代謝検査法を確立する。本研究によって、発症・合併症予測や重症度評価が容易となり、治療戦略の決定や有害事象の予防に寄与することが期待できる。当該年度は以下の研究を実施した。 【MRIによる多角的無侵襲撃脳循環代謝解析法の開発】IVIMでは、昨年度改良した独自の解析ソフトエアと最適化した解析パラメータを用い、IVIM-CBVの精度をアセタゾラミドSPECT-CVRと比較検証した。ASLでは、昨年度開発したHadamard符号化に加え低解像度multiPLDによるATT補正法を新たに実装し、CBFの精度をSPECTと比較検証した。 【MRI撮像法の標準化と解析アルゴリズムの最適化】昨年度開発したQSM-OEF解析ソフトウエアにおいて、磁場強度や機種毎にフィルタリング・血管除去パラメータを最適化した。 【PET・SPECTとの比較によるMRI脳循環代謝検査法の精度検証】CEA術前の慢性脳虚血患者20名およびもやもや病20名に対し、3T MRIを用いてIVIM・ASL・QSM元画像を撮像し、PETまたはSPECTも撮像した。術中・術後イベントや予後についての情報収集を随時行った。また、急性期脳梗塞患者20名に対し、3T MRIを用いてQSM元画像などを撮像し、有害事象や予後についての情報収集を随時行った。
  • マイクロカテーテルのカニュレーション難易度解明と科学的トレーニングシステムの開発
    Japan Society for the Promotion of Science:Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C)
    Date (from‐to) : 2017/04 -2020/03 
    Author : 曽山 武士, 工藤 與亮, 阿保 大介, 作原 祐介
     
    平成29年度は、予備検討として、従来の先端非可動型マイクロカテーテルを使用してカニュレーションできなかった、またはカニュレーションできたが60分以上 を要した標的血管を "Challenging Vessel" と定義し、14のChallenging Vesselに先端非可動型マイクロカテーテルと先端可動型マイクロカテーテルを用いてカ ニュレーションを試みた際の、カニュレーションの成功率とカニュレーションに要する時間を後方視的に解析し、結果を2017年9月のIVR research meeting(東 京)で発表した。この結果については現在論文を執筆中である。 また、実験で使用する血管模型を作成するために、当初は院内に設置されている3Dプリンターを使用する予定であったが、院内の3Dプリンターでは硬い素材で 血管模型を作らざるをえず、より本物の血管に近づけるため、平成29年度の日本IVR学会総会と日本医学放射線学会秋季大会の3Dプリンターのセッションに参加 して、近年開発された柔らかい素材で血管模型を作成する方法を学び、これを作成できるCanon社の3Dプリンター「Form 2」を購入した。 平成30年度は、前年度に購入した3Dプリンター (Foam2/キャノンライフケアソリューションズ)を使用して、柔軟性のある素材で、内腔のある血管模型(中空モデル)の作成方法を確立した。我々が確立したのは、①Dynamic CT(早期動脈相)のDICOM画像をInVesaliusでSTLに変換する、②MeshLabでトリミング&修正する、③Meshmixerで中空構造を作成する、という手順である。この方法により、最大で長径11cmの腹部血管模型を、壁の厚さ0.5mmで作成するに至った。
  • Japan Society for the Promotion of Science:Grants-in-Aid for Scientific Research
    Date (from‐to) : 2016/04 -2019/03 
    Author : Uwano Ikuko, KUDO Kohsuke, YAMASHITA Fumio
     
    We investigated whether oxygen extraction fraction (OEF) maps generated by magnetic resonance quantitative susceptibility mapping (QSM) at high-field MRI enabled detection of OEF changes when compared with those obtained with PET. OEF ratios on QSM-OEF images at 7 Tesla and 3 Tesla MRI showed a good correlation with those on PET-OEF images in patients with unilateral steno-occlusive internal carotid artery/middle cerebral artery lesions, suggesting that noninvasive OEF measurement by MRI can be a substitute for PET. In addition, we found that preoperative QSM-OEF at 7 Tesla could identify patients at risk for cerebral hyperperfusion following carotid endarterectomy, and that the 7 Tesla QSM-OEF at 5 min after acetazolamide administration mostly correlates with hemodynamics in the patients with major cerebral arterial steno-occlusive disease. Moreover, correlations between QSM-OEF and PET-OEF in patients with chronic ischemia were improved when using high-resolution source images.
  • Japan Society for the Promotion of Science:Grants-in-Aid for Scientific Research
    Date (from‐to) : 2014/04 -2017/03 
    Author : Kudo Kohsuke
     
    Signal simulations for the various tissue were conducted using theoretical equations of MRI signals. Good correlations were noted between signal simulation and O-17 phantom signal, and conversion method from MRI signal to O-17 concentration was determined. Based on the MRI scans of normal volunteers, scan method with FSE sequence was established, and development of algorithm for quantitative analysis of cerebral blood flow. Manufacturing of O-17 oxygen was established, and inhalation apparatus of O-17 was designed. Smaller O-17 phantom was created, and MRI scans with animal MRI were performed. Good image contrast was obtained for marmosets with the administration of O-17 water.
  • Japan Society for the Promotion of Science:Grants-in-Aid for Scientific Research
    Date (from‐to) : 2014/04 -2017/03 
    Author : Sakuhara Yusuke
     
    1. The digital phantom method can be used to create various virtual lesions on the displayed ultrasonographic (US) image by altering original data. In addition, The gray scale of the displayed virtual US image might be appropriately adjusted in order to the real US imaging in the clinical situations. 2. Various diseases, such as tumorous lesions, stones, varices, ascites, etc.) can be presented on the virtual US images created by the digital phantom method. 3. Original CT or MR image data can be altered to other images on the display resembling those of US images by the digital phantom method . 4. The digital phantom method might be applied to the training system of the US-guided percutaneous interventional procedures.
  • Japan Society for the Promotion of Science:Grants-in-Aid for Scientific Research
    Date (from‐to) : 2014/04 -2017/03 
    Author : Tha KhinKhin
     
    Electrical conductivity is a property of a material to conduct electric current. Different materials are known to have different electrical conductivity values, ranging from almost zero (insulators) to several million siemens per meter (S/m) (conductors). Living tissues are also reported to have variable electrical conductivity values -- fat and bone have lower values, whereas the cerebrospinal fluid (CSF) and blood have higher values. Tumors, especially malignant ones, are reported to have higher values than the normal tissues. This study aimed at the establishment of noninvasive electrical conductivity measurement technique by using MRI and to evaluate the accuracy of this technique. It was observed that the noninvasive electrical conductivity measurement by MRI was highly repeatable and valid. In addition, the results suggested that information about electrical conductivity can be useful in distinguishing glioblastoma from lower grade gliomas.
  • Japan Society for the Promotion of Science:Grants-in-Aid for Scientific Research Grant-in-Aid for Young Scientists (B)
    Date (from‐to) : 2013/04 -2015/03 
    Author : GOODWIN Jonathan, PARKES Laura, KUDO Kohsuke, SASAKI Makoto
     
    OEF post processing techniques were demonstrated in a healthy population during concious sedation (Goodwin et al 2014). Subsequent work focused on development of CBF measurement using ASL MRI; necessary for developing a combined imaging approach to CMRO2 measurement. However, there were several technical limitations. Initial efforts focused on ASL using 7T MRI, but it became apparent that this approach was no longer available option with our current 7T system. Instead, collaborative work commenced on development of 3T ASL with multi-banding and Look Locker readout. This involved 6 months in the University of Manchester, UK. If successful, this technique would increase brain coverage allow CBF arrival time measurement. A number of experiments were carried out to try and establish this method, in collaboration with Philips engineers, and a number of technical challenges were discovered, which ultimately were not resolved prior to the end of the Kakenhi period. This research is ongoing.
  • Japan Society for the Promotion of Science:Grants-in-Aid for Scientific Research
    Date (from‐to) : 2013/04 -2015/03 
    Author : UWANO Ikuko, KUDO Kohsuke, OGASAWARA Kuniaki, BEPPU Takaaki, SASAKI Makoto
     
    In this study, we evaluated the performance and efficacy for intensity inhomogeneity correction of various sequences of the human brain in 7 Tesla MRI using the extended version of the unified segmentation algorithm, and we found all of these intensity inhomogeneities were successfully corrected and the contrast between different tissue types was maintained after inhomogeneity correction. In addition, we investigated whether oxygen extraction fraction (OEF) maps that were generated with a quantitative susceptibility mapping (QSM) technique at 7 Tesla would demonstrate OEF changes in patients with major cerebrovascular steno-occlusive disease compared with OEF maps that were generated with PET, and as a result the OEF ratios on QSM-OEF maps at 7 Tesla correlated well with those on PET-OEF maps in patients with steno-occlusive cerebrovascular diseases.
  • Japan Society for the Promotion of Science:Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C)
    Date (from‐to) : 2009 -2011 
    Author : 工藤 與亮, 佐々木 真理, 小笠原 邦昭, 寺江 聡
     
    本研究の目的は超高磁場MRI装置による位相画像を用いて、非侵襲的で定量的な脳脊髄血流解析法を開発・臨床応用することである。 既存の複数の3T-MRI装置(GE社、Philips社)を用いた磁化率強調画像の位相画像から酸素飽和度を算出するプログラムを作成し、酸素飽和度の定量値算出及び脳血流変化のマップ化を行った。さらに、酸素飽和度から酸素摂取率(OEF)を算出するプログラムを作成し、呼吸負荷や薬物負荷によりOEFが有意に変化することが確認された。これらの研究成果は国際学会での発表を行い、論文投稿中である。また、内頚動脈狭窄患者でも脳の位相画像を撮像し、安静時でもOEFの上昇が観察されたが、さらにOEFマップ作成のアルゴリズム改良を行っている。今までは2回のMRI撮像を行って位相変化から酸素飽和度やOEFの変化率を算出できていたが、それを1回のMRI撮像で絶対値として値を算出できるようにプログラム・アルゴリズムを改変中である。患者群ではDiamox負荷での経時的変化の撮像も行っており、PETでのOEFマップとの比較や、MRIのASL法による脳血流マップとの比較を行っている。 また、同時に脳血流解析の基礎的検討として数値ファントムを開発し、解析プログラムの精度検証を行っているが、市販ソフトウェアでの解析結果がまとまったので論文作成中である。さらに、各市販ソフトウェアメーカへの結果のフィードバックも行っている。
  • Japan Society for the Promotion of Science:Grants-in-Aid for Scientific Research
    Date (from‐to) : 2008 -2010 
    Author : TERAE Satoshi, INOUE Takeshi, NAKAGAWA Shin, KUDO Kohsuke
     
    Diffusion tensor imaging (DTI) was conducted in 13 treatment-resistant, 12 nontreatment-resistant, and 19 drug-naive patients with major depression. As compared with normal control subjects, a voxel-based analysis revealed significant decrease in fractional anisotropy (FA) in the right frontal white matter in the treatment-resistant patients. Histogram analysis demonstrated significant decrease in peak position of FA histogram of the drug-naive patients. No significant correlation was observed between the FA abnormality and clinical severity as assessed by HDRS, GAF, and MADRS.
  • Japan Society for the Promotion of Science:Grants-in-Aid for Scientific Research
    Date (from‐to) : 2005 -2009 
    Author : SHIRATO Hiroki, KANEKO Junichi, NISHIYAMA Syusuke, KATOH Chietsugu, AOYAMA Hidefumi, SEKI Koh-ichi, ONIMARU Rikiya, NISHIOKA Takeshi, MORITA Koichi, DATE Hiroyuki, TAKADA Eiji, TOMIOKA Satoshi, KUDO Kohsude, ONODERA Yuya, KAMISHIMA Tamotsu, ONIMARU Rikiya, SHIMIZU Shinichi, SAKUHARA Yusuke, OYAMA Noriko, ABO Daisuke, TAGUCHI Hiroshi
     
    We developed a four-dimensional (4-D, space and time) focal positron emission localizer, FPEL, using two sets of BGO scintillators, photo-electric multiplier, and collimators. A narrow (5-mm in diameter) 45-MeV electron beam was controlled to irradiate a target with an accuracy of 0.1mm in 4D coordinates automatically if the amount of positron emitters at the target exceeds the threshold. A mouse model was established to irradiate the tumor in which FDG is accumulated. Using the FPEL, 45-MeV electron beam hit the tumor in mice which move in front of the beam exit with the amplitude resembling human respiration. Tumor without fiducial gold marker disappeared within a week after the irradiation. Basis for 4D stereotacic radiotherapy was established successfully.
  • Japan Society for the Promotion of Science:Grants-in-Aid for Scientific Research
    Date (from‐to) : 2006 -2008 
    Author : SHIRATO Hiroki, HONMA Sato, TAMAKI Nagara, KUGE Yuji, DATE Hiroyuki, KIYANAGI Yoshiaki, HATAKEYAMA Masanori, KANEKO Junichi, MIZUTA Masahiro, INUBUSHI Masayuki, TADANO Shigeru, TAMURA Mamoru, HAYAKAWA Kazushige, MATSUNAGA Naofumi, ISHIKAWA Masayori, AOYAMA Hidefumi, SAKUHARA Yusuke, ONIMARU Rikiya, ABO Daisuke, OITA Masataka, KAMISHIMA Tamotsu, TERAE Satoshi, KUDO Kohsuke, ONODERA Yuya, OMATSU Tokuhiko, SHIMIZU Shinichi, NISHIMURA Takashi, SUZUKI Ryusuke, GERARD Bengua
     
    いままでの先端放射線医療に欠けていた医療機器と患者のinteractionを取り入れた放射線治療を可能にする。臓器の動き・腫瘍の照射による縮小・免疫反応などは、線量と時間に関して非線形であり、システムとしての癌・臓器の反応という概念を加えることが必要であることが示唆された。生体の相互作用を追求していく過程で、動体追跡技術は先端医療のみならず、基礎生命科学でも重要な役割を果たすことがわかった。
  • Japan Society for the Promotion of Science:Grants-in-Aid for Scientific Research
    Date (from‐to) : 2006 -2007 
    Author : TERAE Satoshi, YAMAMOTO Toru, KATOH Chietsugu, KURODA Satoshi, KUDO Kohsuke
     
    Using susceptibility-weighted imaging (SWI) of MRI (magnetic resonance imaging), we tried to develop a method to measure regional oxygen consumption of the brain. We evaluated local inhomogeneity of the magnetic field caused by deoxyhemoglobin (deoxyHb) in the cerebral vein using the phase information of SWI. We found that the local inhomogeneity observed by SWI is strongly affected by an angle between the longitudinal axis of the vein and the direction of the static magnetic field of the MRI unit. Therefore, the angle has to be incorporated to calculate local deoxyHb concentration of the vein. In normal volunteers, the phase shift increased under hyperventilation and it decreased under breath hold. Changes in oxygen saturation of the veins and in cerebral blood flow, that were calculated by using the difference in phase shift, showed the same results. This indicates that we can measure deoxyHb concentration of the cerebral veins by SWI if we can establish a reference of relationship between the amount of phase shift and deoxyHb concentration in the vein. In a patient with acute cerebral infarct, the largest local phase shift was observed in the infracted area. The phase shift was the largest immediately after the onset, and it decreased gradually during the first 20 days. In contrast, in another patient with chronically impaired blood flow and increased oxygen extraction fraction (OEF) in left anterior and middle cerebral artery territory that was caused by left internal carotid artery occlusion, there was no difference in the phase shift between the ischemic area and the contralateral healthy area. These results imply that SWI can detect increased deoxyHb in the veins of acute ischemic area, but cannot detect increased OEF in chronic phase.
  • CT/MR Perfusionにおける定量解析
  • Quantitative CT/MR perfusion analysis of cerebral blood flow

Educational Activities

Teaching Experience

  • Master's Thesis Research in Medical Sciences
    開講年度 : 2021
    課程区分 : 修士課程
    開講学部 : 医学院
    キーワード : 画像診断、CT、MRI、PET、SPECT、血管造影、超音波、IVR、RI内用療法
  • Basic Principles of Medicine
    開講年度 : 2021
    課程区分 : 修士課程
    開講学部 : 医学院
    キーワード : 画像診断、CT、MRI、PET、SPECT、血管造影、超音波、IVR、RI内用療法
  • Inter-Graduate School Classes(Educational Program):Medical AI developer training program (intensive course)
    開講年度 : 2021
    課程区分 : 修士課程
    開講学部 : 大学院共通科目
    キーワード : 医学、医療、AI、機械学習、情報科学、ディープ・ラーニング、数学、統計、臨床研究
  • Inter-Graduate School Classes(Educational Program):Medical AI developer training program (intensive course)
    開講年度 : 2021
    課程区分 : 修士課程
    開講学部 : 大学院共通科目
    キーワード : 医学、医療、AI、ビッグデータ、倫理、IRB、法律、産学連携、臨床研究、プロトコル
  • Inter-Graduate School Classes(Educational Program):Medical AI developer training program (intensive course)
    開講年度 : 2021
    課程区分 : 修士課程
    開講学部 : 大学院共通科目
    キーワード : 医学、医療、AI、ディープ・ニューラル・ネットワーク、倫理、法律、特許、薬事承認
  • Inter-Graduate School Classes(Educational Program):Medical AI developer training program (intensive course)
    開講年度 : 2021
    課程区分 : 修士課程
    開講学部 : 大学院共通科目
    キーワード : 画像診断、AI、CT、MRI、PET、超音波、インターベンショナルラジオロジー、DICOM、プログラミング、定量、遠隔画像診断
  • Inter-Graduate School Classes(Educational Program):Medical AI developer training program (intensive course)
    開講年度 : 2021
    課程区分 : 修士課程
    開講学部 : 大学院共通科目
    キーワード : AI、ゲノム、次世代シークエンサー、遺伝子パネル検査、プリシジョン・メディシン
  • Inter-Graduate School Classes(Educational Program):Medical AI developer training program (intensive course)
    開講年度 : 2021
    課程区分 : 修士課程
    開講学部 : 大学院共通科目
    キーワード : 診断、治療、AI、認知症、動画解析、医薬品開発
  • Inter-Graduate School Classes(Educational Program):Medical AI developer training program (intensive course)
    開講年度 : 2021
    課程区分 : 修士課程
    開講学部 : 大学院共通科目
    キーワード : AI、手術、AI支援手術、動画解析
  • Inter-Graduate School Classes(Educational Program):Medical AI developer training program (intensive course)
    開講年度 : 2021
    課程区分 : 修士課程
    開講学部 : 大学院共通科目
    キーワード : AI、機械学習、ディープ・ラーニング、画像分類、異常検知、画像セグメンテーション、画像生成、画質改善、自然言語処理、プログラミング
  • Inter-Graduate School Classes(Educational Program):Medical AI developer training program (intensive course)
    開講年度 : 2021
    課程区分 : 修士課程
    開講学部 : 大学院共通科目
    キーワード : AI、データ・ハンドリング、DICOM、プログラミング、ディープ・ニューラル・ネットワーク、教師データ、機械学習、性能評価
  • Diagnostic Radiology for Biomedical Science and Engineering
    開講年度 : 2021
    課程区分 : 修士課程
    開講学部 : 医理工学院
    キーワード : 画像診断 CT MRI
  • Radiologic Anatomy for Biomedical Science and Engineering
    開講年度 : 2021
    課程区分 : 修士課程
    開講学部 : 医理工学院
    キーワード : 正常解剖、画像診断、放射線医学 
  • Basic Principles of Medicine
    開講年度 : 2021
    課程区分 : 修士課程
    開講学部 : 医学院
    キーワード : 医学、医療、AI、ディープ・ニューラル・ネットワーク、倫理、法律、特許、薬事承認
  • Basic Principles of Medicine
    開講年度 : 2021
    課程区分 : 修士課程
    開講学部 : 医学院
    キーワード : 医学、医療、AI、機械学習、情報科学、ディープ・ラーニング、数学、統計、臨床研究
  • Basic Principles of Medicine
    開講年度 : 2021
    課程区分 : 修士課程
    開講学部 : 医学院
    キーワード : 医学、医療、AI、ビッグデータ、倫理、IRB、法律、産学連携、臨床研究、プロトコル
  • Basic Principles of Medicine
    開講年度 : 2021
    課程区分 : 修士課程
    開講学部 : 医学院
    キーワード : AI、ゲノム、次世代シークエンサー、遺伝子パネル検査、プリシジョン・メディシン
  • Basic Principles of Medicine
    開講年度 : 2021
    課程区分 : 修士課程
    開講学部 : 医学院
    キーワード : AI、データ・ハンドリング、DICOM、プログラミング、ディープ・ニューラル・ネットワーク、教師データ、機械学習、性能評価
  • Basic Principles of Medicine
    開講年度 : 2021
    課程区分 : 修士課程
    開講学部 : 医学院
    キーワード : AI、手術、AI支援手術、動画解析
  • Basic Principles of Medicine
    開講年度 : 2021
    課程区分 : 修士課程
    開講学部 : 医学院
    キーワード : AI、機械学習、ディープ・ラーニング、画像分類、異常検知、画像セグメンテーション、画像生成、画質改善、自然言語処理、プログラミング
  • Basic Principles of Medicine
    開講年度 : 2021
    課程区分 : 修士課程
    開講学部 : 医学院
    キーワード : 画像診断、AI、CT、MRI、PET、超音波、インターベンショナルラジオロジー、DICOM、プログラミング、定量、遠隔画像診断
  • Basic Principles of Medicine
    開講年度 : 2021
    課程区分 : 修士課程
    開講学部 : 医学院
    キーワード : 診断、治療、AI、認知症、動画解析、医薬品開発
  • Principles of Medicine
    開講年度 : 2021
    課程区分 : 博士後期課程
    開講学部 : 医学院
    キーワード : 画像診断、CT、MRI、PET、SPECT、血管造影、超音波、IVR、RI内用療法
  • Dissertation Research in Medical Sciences
    開講年度 : 2021
    課程区分 : 博士後期課程
    開講学部 : 医学院
    キーワード : 画像診断、CT、MRI、PET、SPECT、血管造影、超音波、IVR、RI内用療法
  • Dissertation Research in Clinical Medicine
    開講年度 : 2021
    課程区分 : 博士後期課程
    開講学部 : 医学院
    キーワード : 画像診断、CT、MRI、PET、SPECT、血管造影、超音波、IVR、RI内用療法
  • Principles of Medicine
    開講年度 : 2021
    課程区分 : 博士後期課程
    開講学部 : 医学院
    キーワード : 画像診断、AI、CT、MRI、PET、超音波、インターベンショナルラジオロジー、DICOM、プログラミング、定量、遠隔画像診断
  • Principles of Medicine
    開講年度 : 2021
    課程区分 : 博士後期課程
    開講学部 : 医学院
    キーワード : 診断、治療、AI、認知症、動画解析、医薬品開発
  • Principles of Medicine
    開講年度 : 2021
    課程区分 : 博士後期課程
    開講学部 : 医学院
    キーワード : 医学、医療、AI、ディープ・ニューラル・ネットワーク、倫理、法律、特許、薬事承認
  • Principles of Medicine
    開講年度 : 2021
    課程区分 : 博士後期課程
    開講学部 : 医学院
    キーワード : 医学、医療、AI、機械学習、情報科学、ディープ・ラーニング、数学、統計、臨床研究
  • Principles of Medicine
    開講年度 : 2021
    課程区分 : 博士後期課程
    開講学部 : 医学院
    キーワード : 医学、医療、AI、ビッグデータ、倫理、IRB、法律、産学連携、臨床研究、プロトコル
  • Principles of Medicine
    開講年度 : 2021
    課程区分 : 博士後期課程
    開講学部 : 医学院
    キーワード : AI、ゲノム、次世代シークエンサー、遺伝子パネル検査、プリシジョン・メディシン
  • Principles of Medicine
    開講年度 : 2021
    課程区分 : 博士後期課程
    開講学部 : 医学院
    キーワード : AI、データ・ハンドリング、DICOM、プログラミング、ディープ・ニューラル・ネットワーク、教師データ、機械学習、性能評価
  • Principles of Medicine
    開講年度 : 2021
    課程区分 : 博士後期課程
    開講学部 : 医学院
    キーワード : AI、手術、AI支援手術、動画解析
  • Principles of Medicine
    開講年度 : 2021
    課程区分 : 博士後期課程
    開講学部 : 医学院
    キーワード : AI、機械学習、ディープ・ラーニング、画像分類、異常検知、画像セグメンテーション、画像生成、画質改善、自然言語処理、プログラミング
  • Nuclear Medicine
    開講年度 : 2021
    課程区分 : 学士課程
    開講学部 : 医学部
    キーワード : 画像診断 PET SPECT IVR 画像定量化 アイソトープ治療
  • Diagonstic Radiology (Normal Anatomy)
    開講年度 : 2021
    課程区分 : 学士課程
    開講学部 : 医学部
    キーワード : 正常解剖 画像診断 放射線医学 

Campus Position History

  • 2021年4月1日 
    2023年3月31日 
    アイソトープ総合センター長
  • 2023年4月1日 
    2024年7月31日 
    アイソトープ総合センター長
  • 2022年4月1日 
    2024年3月31日 
    研究戦略室室員
  • 2022年4月1日 
    2024年3月31日 
    総長補佐

Position History

  • 2021年4月1日 
    2023年3月31日 
    アイソトープ総合センター長
  • 2023年4月1日 
    2024年7月31日 
    アイソトープ総合センター長
  • 2022年4月1日 
    2024年3月31日 
    研究戦略室室員
  • 2022年4月1日 
    2024年3月31日 
    総長補佐


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